The AWS Certified Cloud Practitioner (CLF-C02)

 One of the advantages of AWS Cloud computing is that it minimizes variable costs by leveraging economies of scale. This means that AWS can achieve lower costs per unit of computing resources by spreading the fixed costs of building and maintaining data centers over a large number of customers. As a result, AWS can offer lower and more predictable prices to its customers, who only pay for the resources they consume. Therefore, the correct answer is B. You can learn more about AWS pricing and economies of scale

The company follows the AWS Cloud design principle of ensuring traceability by using AWS CloudTrail. AWS CloudTrail is a service that records the API calls and events made by or on behalf of the AWS account. The company can use AWS CloudTrail to monitor, audit, and analyze the activity and changes in their AWS resources and applications. AWS CloudTrail helps the company to achieve compliance, security, governance, and operational efficiency. Recovering automatically, performing operations as code, and measuring efficiency are other AWS Cloud design principles, but they are not directly related to using AWS CloudTrail. Recovering automatically means that the company can design their cloud workloads to handle failures gracefully and resume normal operations without manual intervention. Performing operations as code means that the company can automate the creation, configuration, and management of their cloud resources using scripts or templates. Measuring efficiency means that the company can monitor and optimize the performance and utilization of their cloud resources and applications34

 Amazon Elastic Container Service (Amazon ECS) is a solution that meets the requirements of deploying and managing a Docker-based application on AWS with the least amount of operational overhead. Amazon ECS is a fully managed container orchestration service that makes it easy to run, scale, and secure Docker container applications on AWS. Amazon ECS eliminates the need for you to install, operate, and scale your own cluster management infrastructure. With simple API calls, you can launch and stop container-enabled applications, query the complete state of your cluster, and access many familiar features likesecurity groups, Elastic Load Balancing, EBS volumes, and IAM roles3.

 According to the AWS shared responsibility model, AWS is responsible for the security of the cloud, while the user is responsible for the security in the cloud. This means that AWS manages the security and maintenance of the underlying infrastructure, such as the servers, networks, and operating systems, while the user manages the security and configuration of the resources and applications that run on AWS. For AWS Lambda functions, the tasks that are the user’s responsibility are:

Establish the IAM permissions that define who can run the Lambda functions. IAM is a service that enables users to manage access and permissions for AWS resources and users. Users can create IAM policies, roles, and users to grant or deny permissions to run Lambda functions, invoke other AWS services, or access AWS resources from Lambda functions. [AWS Lambda Permissions] AWS Certified Cloud Practitioner - aws.amazon.com

Write the code for the Lambda functions to define the application logic. Lambda functions are units of code that can be written in any supported programming language, such as Python, Node.js, Java, or Go. Users can write the code for the Lambda functions using the AWS Management Console, the AWS Command Line Interface (AWS CLI), the AWS SDKs, or any code editor of their choice. Users can also use AWS Lambda Layers to share and manage common code and dependencies across multiple functions. [AWS Lambda Overview]  AWS Certified Cloud Practitioner - aws.amazon.com

The company can use AWS Organizations to track the combined AWS usage costs of all of its linked accounts. AWS Organizations is a service that enables you to consolidate multiple AWS accounts into an organization that you can manage centrally. You can use AWS Organizations to create a consolidated billing report that shows the charges incurred by each account in your organization as well as the total charges across all accounts. You can also use AWS Organizations to apply policies and controls to your accounts to help you manage costs and security5.

 Amazon Relational Database Service (Amazon RDS) is the AWS service that the company should use to migrate its Microsoft SQL Server database management system from on premises to the AWS Cloud. Amazon RDS is a fully managed service that provides a scalable, secure, and high-performance relational database platform. Amazon RDS supports several database engines, including Microsoft SQL Server. Amazon RDS reduces the management overhead for the database environment by taking care of tasks such as provisioning, patching, backup, recovery, andmonitoring. For more information, see What is Amazon Relational Database Service (Amazon RDS)? and Amazon RDS for SQL Server.

Amazon CloudFront with Amazon S3 is a solution that allows you to provide static files securely to users from around the world. Amazon CloudFront is a fast content delivery network (CDN) service that securely delivers data, videos, applications, and APIs to customers globally with low latency, high transfer speeds, all within a developer-friendly environment. Amazon S3 is an object storage service that offers industry-leading scalability, data availability, security, and performance. You can use Amazon S3 to store and retrieve any amount of data from anywhere. You can also configure Amazon S3 to work with Amazon CloudFront to distribute your content to edge locations near your users for faster delivery and lower latency. Amazon Kinesis Data Streams is a service that enables you to build custom applications that process or analyze streaming data for specialized needs. This option is not relevant for providing static files securely. Amazon EC2 instances with an Application Load Balancer is a solution that allows you to distribute incoming traffic across multiple targets, such as EC2 instances, in multiple Availability Zones. This option is suitable for dynamic web applications, but not necessary for static files. Amazon Elastic File System (Amazon EFS) is a service that provides a simple, scalable, fully managed elastic NFS file system for use with AWS Cloud services and on-premises resources. This option is not relevant for providing static files securely.

Creating an IAM role with the required permissions and attaching the role to the EC2 instance is the most operationally efficient solution to delegate permissions. An IAM role is an entity that defines a set of permissions for making AWS service requests. An IAM role can be assumed by an EC2 instance to access other AWS resources, such as Amazon S3 and Amazon DynamoDB, without having to store any credentials on the instance. This solution is more secure and scalable than using IAM users and their access keys. For more information, see [IAM Roles for Amazon EC2] and [Using an IAM Role to Grant Permissions to Applications Running on Amazon EC2 Instances] .

 Amazon DynamoDB is the AWS service that will meet the requirement of building an application that will receive millions of database queries each second. Amazon DynamoDB is a fully managed NoSQL database service that provides fast and consistent performance, scalability, and durability. Amazon DynamoDB can handle any level of request traffic and automatically scale up or down the capacity based on the demand. Amazon DynamoDB also supports in-memory caching with Amazon DynamoDB Accelerator (DAX) to improve the response time and reduce the cost. For more information, see What is Amazon DynamoDB? and Amazon DynamoDB Features.