A company is running a Docker application on Amazon ECS. The application must scale based on user load in the last 15 seconds.
How should a Developer instrument the code so that the requirement can be met?

A. Create a high-resolution custom Amazon CloudWatch metric for user activity data, then publish data every 30 seconds
B. Create a high-resolution custom Amazon CloudWatch metric for user activity data, then publish data every 5 seconds
C. Create a standard-resolution custom Amazon CloudWatch metric for user activity data, then publish data every 30 seconds
D. Create a standard-resolution custom Amazon CloudWatch metric for user activity data, then publish data every 5 seconds