Which of the following security policies is BEST to use when trying to mitigate the risks involved with allowing a user to access company email via their cell phone?

A.
The cell phone should require a password after a set period of inactivity.

B.
The cell phone should only be used for company related emails.

C.
The cell phone data should be encrypted according to NIST standards.

D.
The cell phone should have data connection abilities disabled.