Exam AWS Certified SysOps Administrator - Associate topic 1 question 419 discussion

https://aws.amazon.com/blogs/mt/enhance-cloudwatch-metrics-with-metric-math-functions/

Direct Correlation: The number of messages in the SQS queue directly correlates to the workload of the worker processes. By scaling based on this metric, you ensure that you have enough instances to handle the incoming messages. Metric Math Expression: CloudWatch metric math allows you to calculate the average number of messages per instance. This helps you make informed scaling decisions based on the workload distribution. Target Tracking Scaling: This policy automatically adjusts the number of instances in the Auto Scaling group based on the target value you set for the metric math expression. This ensures that your worker processes can handle the fluctuating message volume.

think its C

B is correct; Metric math expression for the SQS queue: By using CloudWatch to create a metric math expression, you can calculate the approximate number of messages visible in the SQS queue for each instance. This metric provides insights into the workload on each EC2 instance and can be used to make scaling decisions. Creating a target tracking scaling policy for this metric allows the Auto Scaling group to automatically adjust the number of instances based on the calculated metric, ensuring that there are enough instances to handle the increased number of messages.