Which of the following are ways to improve security on AWS?

Explanations:

AWS Artifact is a service that provides access to compliance reports and security documentation, but it does not directly improve security on AWS. It is primarily a resource for managing compliance information rather than a security enhancement tool.

Granting the broadest permissions to all IAM roles is a poor security practice. It increases the risk of unauthorized access and potential misuse of resources. Security best practices recommend the principle of least privilege, which means granting only the permissions necessary for a role to perform its function.

Running application code with AWS Cloud is too vague to determine its impact on security. While using AWS services can improve security through managed services, the statement lacks specificity about security measures. The security of the application also depends on how it is coded and configured.

Enabling multi-factor authentication (MFA) with Amazon Cognito enhances security by requiring users to provide two or more verification factors to gain access, which significantly reduces the risk of unauthorized access.

Using AWS Trusted Advisor security checks helps identify potential security vulnerabilities and recommends best practices, thus actively contributing to the overall security posture of an AWS environment.