You have a SharePoint Server 2010 Service Pack 1 (SP1) server farm. You discover that each Unified
Logging Service (ULS) log contains only 30 minutes of data. You need to configure the ULS logs to
contain 60 minutes of activity. Which Windows PowerShell cmdlet should you use?

A.
Set-SPDiagnosticConfig

B.
Set-SPUsageService

C.
Set-SPLogLevel

D.
Set-SPTimerJob

Explanation:
Ref: http://technet.microsoft.com/en-us/library/ff607575.aspx