You need to identify the size of Collection1

You have a SharePoint Server 2013 Service Pack 1 (SP1) server farm. The farm contains a
site collection named Collection1. Collection1 has a quota of 100 GB and a dedicated
database.
You need to identify the size of Collection1.
What should you use?

A.
Site Web Analystics reports

B.
Site collection Web Analytics reports

C.
administrative reports

D.
Unified Logging Service (ULS) logs

Explanation:
Site Collection Web Analytics provides a report called Storage Usage at: _layouts/WebAnalytics/Report.aspx?
t=StorageTrendsReport&l=sc
It shows the trend in storage growth for the entiresite collection against the quota, but doesn’t drill down to
lower levels.