You need to configure Microsoft Lync Online to disable alerts for voicemail and instant messages to Windows Phones

You are the Office 365 administrator for your company.
You need to configure Microsoft Lync Online to disable alerts for voicemail and instant messages to
Windows Phones.
What should you do?

A.
Use the Set-CsHostedVoiceMailPolicy Windows PowerShell cmdlet.

B.
Use the Set-CsPushNotificationConfiguration Windows PowerShell cmdlet.

C.
In the Lync admin center, select the Display presence information only to a user’s contacts option.

D.
Use the Set-CsUser Windows PowerShell cmdlet.

Explanation:
http://technet.microsoft.com/en-us/library/dn362807.aspx