An application has been built with Amazon EC2 instances that retrieve messages from Amazon SQS.

The correct answer is B and E. To troubleshoot the issue, the security engineer should verify that the SQS resource policy does not explicitly deny access to the role used by the instances, and that the role attached to the instances contains policies that allow access to the queue. These actions will ensure that the instances have the necessary permissions to retrieve messages from Amazon SQS, while maintaining the principle of least privilege.

The other options are incorrect because they are either unnecessary or overly permissive. Option A is incorrect because configuring and assigning an MFA device to the role used by the instances is not required to access Amazon SQS. MFA is an optional security feature that adds an extra layer ofprotection on top of the user name and password1. Option C is incorrect because verifying that the access key attached to the role used by the instances is active is not relevant to the issue. Access keys are used to make programmatic requests to AWS services, not to retrieve messages from Amazon SQS2. Option D is incorrect because attaching the AmazonSQSFullAccess managed policy to the role used by the instances is overly permissive and violates the principle of least privilege. This policy grants full access to all Amazon SQS actions and resources, which may expose the instances to unnecessary risks3.