Which of the following items listed can AWS Cloudwatch monitor?

You have been asked to set up monitoring of your network and you have decided that Cloudwatch would be the best service to use. Amazon CloudWatch monitors your Amazon Web Services (AWS) resources and the applications you run on AWS in real-time. You can use CloudWatch to collect and track metrics, which are the variables you want to measure for your resources and applications.

Which of the following items listed can AWS Cloudwatch monitor?
A . Log files your applications generate.
B . All of the items listed on this page.
C . System-wide visibility into resource utilization, application performance, and operational health.
D . Custom metrics generated by your applications and services.

Answer: B

Explanation:

Amazon CloudWatch can monitor AWS resources such as Amazon EC2 instances, Amazon DynamoDB tables, and Amazon RDS DB instances, as well as custom metrics generated by your applications and services, and any log files your applications generate. You can use Amazon CloudWatch to gain system-wide visibility into resource utilization, application performance, and operational health. You can use these insights to react and keep your application running smoothly.

Reference: http://aws.amazon.com/cloudwatch/