what should you view?

You are the Office 365 administrator for your company.
Users report that they have received significantly more spam messages over the past month than
they normally receive.
You need to analyze trends for the email messages received over the past 60 days.
From the Office 365 admin center, what should you view?

A.
the Mail protection reports

B.
the Office 365 Malware detections in received mail report

C.
messages on the Message center page

D.
the Mailbox access by non-owners report

Explanation:
Use mail protection reports in Office 365 to view data about malware, spam, and rule detections.
If you’re an Exchange Online or Exchange Online Protection (EOP) admin, there’s a good chance
you’d like to monitor how much spam and malware is being detected, or how often your transport
rules are being matched. With the interactive mail protection reports in the Office 365 admin center,
you can quickly get a visual report of summary data, and drill-down into details about individual
messages, for as far back as 90 days.

https://technet.microsoft.com/en-us/library/dn500744(v=exchg.150).aspx