Top AWS Foundations, Compute, and Storage MCQs for Interview Preparation
Prepare for your cloud and DevOps interviews with these carefully selected AWS Foundations, Compute, and Storage MCQs. This set covers core AWS services, EC2 concepts, storage options, and fundamental cloud principles. Each question includes clear answers and explanations to help you strengthen your understanding and boost interview confidence.
By the end of this article, you’ll be well-equipped to handle a variety of AWS Foundation, Compute, and Storage interview questions and demonstrate your proficiency in automating IT tasks efficiently and effectively.
1. What does the acronym AWS stand for ?
A) Amazon Web Solutions
B) Amazon Web Services
C) Advanced Web Systems
D) Automated Web Services
Correct Answer: B
Explanation: Amazon Web Services (AWS) is a comprehensive cloud computing platform provided by Amazon. It offers a wide range of services including computing power, storage, and networking.
2. In which year was AWS officially launched with services like S3 and EC2 ?
A) 2002
B) 2004
C) 2006
D) 2010
Correct Answer: C
Explanation: AWS officially launched in 2006, revolutionizing cloud infrastructure. The initial core services included storage, computing, and messaging.
3. Which cloud model provides virtualized computing resources like servers and storage over the internet ?
A) SaaS
B) PaaS
C) IaaS
D) FaaS
Correct Answer: C
Explanation: Infrastructure as a Service (IaaS) provides the foundational building blocks for cloud IT, such as virtual machines and networking. AWS EC2 is a prime example of an IaaS offering.
4. What is the primary benefit of the “Pay-as-you-go” pricing model ?
A) Fixed monthly fees
B) Paying only for the resources consumed
C) Large upfront investments
D) Unlimited free usage
Correct Answer: B
Explanation: AWS allows users to pay only for the resources they actually use, which eliminates the need for significant upfront hardware investments. This helps businesses scale and grow rapidly without financial waste.
5. Under the Shared Responsibility Model, what is AWS responsible for ?
A) Data encryption
B) Security “of” the cloud infrastructure
C) Managing guest operating systems
D) IAM user permissions
Correct Answer: B
Explanation: AWS is responsible for the security of the global infrastructure, including physical data centers and hardware. Customers are responsible for security “in” the cloud, such as their own data and application security.
6. What is an AWS Region ?
A) A single data center
B) A collection of edge locations
C) A separate geographical area containing multiple Availability Zones
D) A virtual private network
Correct Answer: C
Explanation: An AWS Region is a geographical area that contains multiple, isolated locations known as Availability Zones. Regions are separate from each other to enhance data sovereignty and fault tolerance.
7. How many Availability Zones (AZs) are typically found within a single AWS Region ?
A) Exactly one
B) Only two
C) Multiple (at least one or more)
D) Zero
Correct Answer: C
Explanation: Each AWS Region consists of several isolated locations known as Availability Zones. These zones are connected via high-speed fiber networks to ensure low latency and high availability.
8. What is the primary purpose of an Availability Zone (AZ) ?
A) To reduce billing costs
B) To provide fault tolerance and high availability within a region
C) To store long-term archives only
D) To manage DNS records
Correct Answer: B
Explanation: AZs are designed to be isolated from failures in other zones within the same region. This allows users to build resilient applications that stay operational even if one data center building fails.
9. Which service provides resizable virtual servers in the cloud ?
A) Amazon S3
B) Amazon EC2
C) AWS Lambda
D) Amazon RDS
Correct Answer: B
Explanation: Amazon Elastic Compute Cloud (EC2) provides scalable compute capacity in the form of virtual servers called instances. Users have complete control over the operating system and software installed on these instances.
10. What is an Amazon Machine Image (AMI) ?
A) A hardware device
B) A pre-configured template for launching EC2 instances
C) A type of database engine
D) A network security rule
Correct Answer: B
Explanation: An AMI provides the information required to launch a virtual server, including the operating system and required software. It acts as the fundamental unit of deployment for EC2.
11. Which EC2 instance type is ideal for workloads that need to burst to higher performance ?
A) C-family (Compute Optimized)
B) T-family (Burstable Performance)
C) R-family (Memory Optimized)
D) I-family (Storage Optimized)
Correct Answer: B
Explanation: T-family instances provide a baseline level of CPU performance with the ability to burst above that baseline when needed. They are often used for small to medium applications with variable traffic.
12. What happens to the data in an EC2 instance store volume if the instance is terminated ?
A) It is automatically backed up to S3
B) It is permanently lost
C) It is moved to an EBS volume
D) it remains accessible in the console
Correct Answer: B
Explanation: Instance store volumes provide temporary block-level storage that is physically attached to the host machine. The data in these volumes is lost if the instance is stopped or terminated.
13. Which service is a serverless compute option that runs code in response to events ?
A) Amazon EC2
B) AWS Lambda
C) Amazon Lightsail
D) AWS Batch
Correct Answer: B
Explanation: AWS Lambda allows users to run code without provisioning or managing servers. It automatically scales based on the number of incoming requests and charges only for compute time used.
14. What is the maximum execution time for a single AWS Lambda function invocation ?
A) 1 minute
B) 5 minutes
C) 15 minutes
D) 1 hour
Correct Answer: C
Explanation: Lambda functions are designed for short-lived tasks and have a maximum execution time limit of 15 minutes. This makes them ideal for event-driven processing rather than long-running applications.
15. Which service helps you easily deploy and manage web applications without worrying about infrastructure ?
A) AWS CloudFormation
B) AWS Elastic Beanstalk
C) Amazon VPC
D) Amazon Route 53
Correct Answer: B
Explanation: AWS Elastic Beanstalk is a Platform as a Service (PaaS) that handles deployment, including capacity provisioning and load balancing. Developers can simply upload their code, and the service manages the rest.
16. What is Amazon S3 primarily used for ?
A) Running virtual machines
B) Object storage for data like images, videos, and backups
C) Managed relational databases
D) Dedicated network connections
Correct Answer: B
Explanation: Amazon Simple Storage Service (S3) is an object storage service designed to store and retrieve any amount of data from anywhere on the web. It is commonly used for backups, static website hosting, and big data analytics.
17. What is the theoretical maximum size of a single object that can be stored in Amazon S3 ?
A) 100 GB
B) 1 TB
C) 5 TB
D) Unlimited
Correct Answer: C
Explanation: While S3 can store virtually unlimited total amounts of data, individual objects can range from 0 bytes up to 5 Terabytes. Large files over 100 MB should be uploaded using the multi-part method for efficiency.
18. Which S3 storage class is best for data that is accessed infrequently but requires millisecond access ?
A) S3 Standard
B) S3 Standard-IA (Infrequent Access)
C) S3 Glacier Flexible Retrieval
D) S3 One Zone-IA
Correct Answer: B
Explanation: S3 Standard-IA is designed for data that is accessed less frequently but still needs rapid access when requested. It offers lower storage costs than Standard but higher retrieval fees.
19. What is the purpose of S3 Lifecycle Policies ?
A) To encrypt data automatically
B) To automate the transition of objects to cheaper storage classes over time
C) To monitor S3 bucket traffic
D) To prevent accidental deletion of buckets
Correct Answer: B
Explanation: Lifecycle policies allow users to define rules to move data to lower-cost storage like Glacier or delete it after a certain period. This helps optimize storage costs based on the age of the data.
20. Which service provides persistent block-level storage volumes for EC2 instances ?
A) Amazon S3
B) Amazon EBS (Elastic Block Store)
C) Amazon EFS (Elastic File System)
D) Amazon Glacier
Correct Answer: B
Explanation: Amazon EBS acts like a physical hard drive for EC2 instances, providing durable storage that persists even if the instance is stopped. These volumes are specifically designed to be attached to a single instance in the same AZ.
21. What is the main difference between EBS and S3 ?
A) EBS is object storage; S3 is block storage
B) EBS is attached to EC2 instances; S3 is accessed via the internet
C) S3 is only for databases; EBS is for web content
D) EBS has higher durability than S3
Correct Answer: B
Explanation: EBS provides block storage that functions like a local drive for a specific EC2 instance. S3 provides object storage that is accessible via REST APIs and web interfaces from anywhere.
22. Which service provides a scalable, managed file system that can be shared across thousands of EC2 instances ?
A) Amazon EBS
B) Amazon EFS (Elastic File System)
C) Amazon S3
D) Amazon DynamoDB
Correct Answer: B
Explanation: Amazon EFS supports the Network File System (NFS) protocol, allowing multiple instances to access the same data concurrently. It scales automatically as files are added or removed.
23. What is the primary use case for Amazon S3 Glacier ?
A) Hosting high-traffic websites
B) Real-time data processing
C) Long-term, low-cost data archiving
D) Running NoSQL queries
Correct Answer: C
Explanation: Amazon Glacier is optimized for infrequently accessed data that requires long-term retention for compliance or backup. It offers significantly lower storage costs than standard S3 classes.
24. Which AWS service is designed to physically transport petabytes of data into the cloud using a secure appliance ?
A) AWS Direct Connect
B) Amazon CloudFront
C) AWS Snowball
D) AWS DataSync
Correct Answer: C
Explanation: AWS Snowball is a physical storage device used to move massive amounts of data in and out of AWS, bypassing network limitations. It is often cheaper and faster than transferring petabyte-scale data over the internet.
25. What is an IAM User ?
A) A set of temporary permissions
B) An identity with long-term credentials representing a person or application
C) A collection of multiple AWS accounts
D) A virtual firewall for EC2
Correct Answer: B
Explanation: An IAM User is an AWS identity with permanent credentials (like a username and password) used to interact with AWS services directly. They are typically created for individuals within an organization.
26. What is the best practice for granting permissions in IAM ?
A) Grant full administrator access to all users
B) Use the Principle of Least Privilege
C) Share a single set of access keys among the team
D) Never use IAM roles
Correct Answer: B
Explanation: Organizations should follow the principle of least privilege, granting only the minimum permissions necessary for a specific task. This reduces security risks by limiting access to sensitive resources.
27. What is an IAM Role ?
A) A person with a password
B) An identity that provides temporary security credentials
C) A group of multiple IAM users
D) A policy written in HTML
Correct Answer: B
Explanation: Unlike users, IAM roles do not have permanent passwords and are assumed by trusted entities like EC2 instances or Lambda functions. They provide temporary access to AWS resources securely.
28. Which IAM feature requires a second form of authentication, such as a code from a physical device ?
A) IAM Roles
B) Multi-Factor Authentication (MFA)
C) Service Control Policies (SCPs)
D) Resource Tagging
Correct Answer: B
Explanation: MFA adds an extra layer of security by requiring users to provide a unique code from a device in addition to their password. This helps protect accounts from unauthorized access even if a password is stolen.
29. What is an Amazon VPC ?
A) A managed database service
B) A logically isolated section of the AWS cloud to launch resources in a virtual network
C) A physical server located on-premises
D) A content delivery network
Correct Answer: B
Explanation: Amazon Virtual Private Cloud (VPC) lets you define a virtual network where you control IP ranges, subnets, and routing. It provides a secure and isolated environment for your AWS resources.
30. What is the difference between a Public and a Private subnet in a VPC ?
A) Public subnets cost more than private subnets
B) Public subnets have a direct route to the internet; private subnets do not
C) Private subnets are only for storage; public are for compute
D) There is no difference
Correct Answer: B
Explanation: A public subnet is associated with an Internet Gateway, allowing instances to have public IP addresses and internet access. Private subnets are isolated from the direct internet and are used for sensitive resources like databases.
31. Which VPC component allows a private subnet to access the internet for updates while blocking incoming requests ?
A) Internet Gateway
B) NAT Gateway
C) VPC Peering
D) Route 53
Correct Answer: B
Explanation: A NAT Gateway enables instances in a private subnet to connect to the internet but prevents the internet from initiating a connection with those instances. It relays outbound traffic through the public subnet’s internet gateway.
32. What is a Security Group in AWS ?
A) A virtual firewall that controls traffic at the EC2 instance level
B) A group of IAM users
C) A physical lock on a data center rack
D) A way to group multiple S3 buckets
Correct Answer: A
Explanation: Security groups act as stateful firewalls for EC2 instances, allowing you to define rules for inbound and outbound traffic based on IP and port. They are associated directly with instances to control who can communicate with them.
33. What does it mean that Security Groups are “stateful” ?
A) They remember the data stored in the instance
B) They require manual restarts to update rules
C) They only work within a single US state
D) Inbound traffic responses are automatically allowed regardless of outbound rules
Correct Answer: D
Explanation: Because security groups are stateful, if you allow an incoming request, the response traffic is automatically permitted to flow back out. This simplifies rule management compared to stateless firewalls.
34. Which service acts as a global Content Delivery Network (CDN) to speed up content distribution ?
A) Amazon Route 53
B) Amazon CloudFront
C) AWS Direct Connect
D) Amazon S3
Correct Answer: B
Explanation: Amazon CloudFront uses a global network of edge locations to cache copies of content closer to end-users. This reduces latency and improves load times for static and dynamic web content.
35. What is Amazon Route 53 ?
A) A managed database service
B) A scalable Domain Name System (DNS) web service
C) A storage device for large data transfers
D) A machine learning tool
Correct Answer: B
Explanation: Route 53 translates human-readable domain names (like www.example.com) into numeric IP addresses. It also supports domain registration and health checks for resources.
36. Which AWS service helps distribute incoming traffic across multiple targets like EC2 instances ?
A) Elastic Load Balancing (ELB)
B) Amazon Route 53
C) AWS Auto Scaling
D) Amazon CloudFront
Correct Answer: A
Explanation: ELB automatically distributes application traffic across multiple targets in different Availability Zones to ensure high availability. It helps avoid overloading a single server and routes around unhealthy targets.
37. What is the primary function of AWS Auto Scaling ?
A) To automatically encrypt all data
B) To adjust the number of EC2 instances based on demand
C) To change the pricing of services in real-time
D) To move data between regions
Correct Answer: B
Explanation: Auto Scaling ensures that you have the right number of instances to handle the current load, launching new ones during spikes and terminating them when demand drops. This optimizes both performance and cost.
38. Which service is a managed relational database service that supports engines like MySQL and PostgreSQL ?
A) Amazon DynamoDB
B) Amazon ElastiCache
C) Amazon Redshift
D) Amazon RDS
Correct Answer: D
Explanation: Amazon Relational Database Service (RDS) simplifies the setup and scaling of structured databases in the cloud. It handles routine tasks like backups, patching, and recovery automatically.
39. What is the key difference between RDS and DynamoDB ?
A) RDS is for SQL; DynamoDB is for NoSQL
B) DynamoDB is only for small datasets
C) RDS is serverless; DynamoDB requires managing servers
D) RDS does not support backups
Correct Answer: A
Explanation: RDS supports structured data and SQL querying for relational databases. DynamoDB is a fully managed NoSQL service designed for high scalability and low-latency key-value data.
40. Which service provides an exabyte-scale data warehouse for high-performance analytics ?
A) Amazon RDS
B) Amazon Aurora
C) Amazon Redshift
D) Amazon DynamoDB
Correct Answer: C
Explanation: Amazon Redshift is optimized for large-scale data analytics, allowing organizations to run complex queries against massive datasets quickly. It uses a columnar storage architecture for high efficiency.
41. What is Amazon CloudWatch used for ?
A) Auditing API calls
B) Monitoring metrics and logs for AWS resources and applications
C) Managing encryption keys
D) Creating virtual networks
Correct Answer: B
Explanation: CloudWatch provides real-time insights by tracking performance metrics like CPU usage and memory. Users can set alarms to trigger automated actions if certain thresholds are met.
42. Which service records AWS API calls and account activity for security auditing ?
A) AWS CloudTrail
B) Amazon CloudWatch
C) AWS Config
D) AWS Trusted Advisor
Correct Answer: A
Explanation: CloudTrail provides a history of API actions taken in an AWS account, recording who did what and when. This is essential for governance, compliance, and operational auditing.
43. What is AWS CloudFormation ?
A) A weather forecasting service
B) A managed email service
C) A way to manage physical hardware
D) An Infrastructure as Code (IaC) service for provisioning resources via templates
Correct Answer: D
Explanation: CloudFormation allows users to define their entire AWS infrastructure in JSON or YAML templates. This automates the deployment and management of resource stacks consistently.
44. Which service provides a dedicated, private network connection from on-premises to AWS ?
A) AWS VPN
B) Amazon Route 53
C) AWS Direct Connect
D) AWS Transit Gateway
Correct Answer: C
Explanation: Direct Connect establishes a physical, dedicated link that bypasses the public internet. This provides more consistent network performance and lower latency for hybrid cloud environments.
45. What is an AWS “Edge Location” ?
A) A main AWS region
B) A private subnet
C) A place where physical hardware is sold
D) A data center used by CloudFront to cache content closer to users
Correct Answer: D
Explanation: Edge locations are smaller data centers located globally, primarily used for content delivery through CloudFront. They help reduce latency by serving content from the site nearest to the user.
46. What is the purpose of AWS Trusted Advisor ?
A) To manage user passwords
B) To encrypt S3 buckets
C) To provide recommendations for cost optimization, security, and performance
D) To host code repositories
Correct Answer: C
Explanation: Trusted Advisor inspects your AWS environment and suggests ways to save money, improve performance, and enhance security. It checks for underutilized resources and security gaps.
47. Which service is a managed NoSQL database capable of single-digit millisecond performance at any scale ?
A) Amazon Aurora
B) Amazon DocumentDB
C) Amazon RDS
D) Amazon DynamoDB
Correct Answer: D
Explanation: DynamoDB is a high-performance NoSQL database that scales automatically to handle massive traffic peaks. It is commonly used for real-time applications like gaming leaderboards and IoT.
48. What is the primary benefit of the AWS Free Tier ?
A) It allows new users to explore AWS services for free within certain limits
B) It gives users unlimited free servers forever
C) It eliminates all data transfer charges
D) It provides free physical hardware
Correct Answer: A
Explanation: The Free Tier program helps individuals and organizations experiment with AWS by offering a limited set of resources for free for a specified period. For example, users can run a t2.micro instance for 750 hours a month for the first year.
49. Which service is an automated security assessment tool for EC2 instances ?
A) AWS Shield
B) Amazon Macie
C) AWS WAF
D) AWS Inspector
Correct Answer: D
Explanation: AWS Inspector automatically assesses applications for vulnerabilities and deviations from security best practices. It generates reports that highlight findings and suggest remediation steps.
50. What is a “Bastion Host” ?
A) A secure instance used as a gateway to access private resources via SSH/RDP
B) A managed database
C) A storage device for large backups
D) A type of load balancer
Correct Answer: A
Explanation: A bastion host is placed in a public subnet to act as a bridge for managing instances in a private subnet securely. This minimizes the attack surface by ensuring private instances are not directly exposed to the internet.
