AWS Certified SysOps Administrator SOA-C01 – Question601

A company is deploying a legacy web application on Amazon EC2 instances behind an ELB Application Load Balancer. The application worked well in the test environment. However, in production, users report that they are prompted to log in to the system several times an hour.
Which troubleshooting step should be taken to help resolve the problem reported by users?

A.
Confirm that the Application Load Balancer is in a multi-AZ configuration.
B. Enable health checks on the Application Load Balancer.
C. Ensure that port 80 is configured on the security group.
D. Enable sticky sessions on the Application Load Balancer.