Answer: D & E;

IAM Best Practices:

-Configure a Strong Password Policy for Your Users

-If you allow users to change their own passwords, require that they create strong passwords and that they rotate their passwords periodically.

-Enable MFA

Reference: https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html

Answer is B & E because AWS Glacier is for archiving long term data that do not need to be changed frequently

Answer is A. According to https://aws.amazon.com/rds/aurora/

"...Amazon Aurora is a relational database management system (RDBMS) built for the cloud with full MySQL and PostgreSQL compatibility..."

"...flexible and auto scaling compute..."

C is NOT correct because DynamoDB is NoSQL database.

B is NOT correct because Amazon Redshift belongs to "Big Data as a Service" category of the tech stack, while MySQL can be primarily classified under "Databases".

D is NOT correct because Amazon ElastiCache is a cache-as-a-service.

Answer is A - Each Availability Zone is isolated, but the Availability Zones in a Region are connected through low-latency links.

C - is incorrect, as a Region consists of multiple AZ, and the question says - "one or more".

D is the only correct answer.

Service such as Amazon Elastic Compute Cloud (Amazon EC2) is categorized

as Infrastructure as a Service (IaaS) and,

as such, requires the customer to perform all of the necessary security configuration and management tasks.

Customers that deploy an Amazon EC2 instance are responsible for management of the guest operating system (

including updates and security patches), any application software or utilities

installed by the customer on the instances,

and the configuration of the AWS-provided firewall (called a security group) on each instance.

That is probably because AWS hosts AZ instances across 2 or more interconnected DC's at least,

unlike Azure, where AZ is "another rack" in same DC, therefore answer B might be logical enough.

Answer is C,

Focus on projects that differentiate your business, not the infrastructure.

Cloud computing lets you focus on your own customers, rather than on the heavy lifting of racking, stacking, and powering servers.

A as with glacier retrieval is not immediate

- you need to wait a minimum of 3 min with expedited retrieval, with EBS you will have to Mount it on an EC2 (therefore not least cost), instance store - ephemeral storage so backup will be lost

The answer should be B - Access keys.

D - SSH keys is needed to direct connect and login into an EC2 instance, not to use AWS Services through CLI.

Reference:

https://aws.amazon.com/dynamodb/