Trick:

it is safe to say whenever the question is about a comparison between on-premises and cloud costs the answer is TCO.

A & B is correct.

The link: https://aws.amazon.com/partners/aws-marketplace/

states that:

"Amazon Machine Image (AMI): Offering an AMI is the preferred option for listing products in AWS Marketplace. Partners have the option for free or paid products. Partners can offer paid products charged by the hour or month. Bring Your Own License (BYOL) is also available and enables customers with existing software licenses to easily migrate to AWS."

Loosely coupled architectures reduce interdependencies, so that a change or failure in a component does not cascade to other components.

Reference:

https://aws-certified-cloud-practitioner.fandom.com/wiki/1.3_List_the_different_cloud_architecture_design_principles

Reference:

https://aws.amazon.com/compliance/shared-responsibility-model/

D:

AWS Config is a service that enables you to assess, audit, and evaluate the configurations of your AWS resources.

Config continuously monitors and records your AWS resource configurations and allows you to automate the evaluation of recorded configurations against desired configurations.

https://aws.amazon.com/compliance/shared-responsibility-model/

Configuration Management – AWS maintains the configuration of its infrastructure devices, but a customer is responsible for configuring their own guest operating systems, databases, and applications.

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.

Reference:

https://aws.amazon.com/cloudfront/

The answer is C.

Elasticity is very similar to Scalability and sometimes it trickier to choose, but not the case here.

Reference:

https://aws.amazon.com/premiumsupport/knowledge-center/report-aws-abuse/