Which diagnostic log should you review?

A company deploys the Azure Application Gateway Web Application Firewall (WAF) to protect their web applications.

Users in a remote office location report the following issues:

– Unable to access part of a web application.

– Part of the web application is failing to load.

– Parts of the web application has activities that are not performing as expected.

You need to troubleshoot the issue.

Which diagnostic log should you review?
A . Performance
B . Firewall
C . Access
D . Azure Activity