which CSS is used for calling privileges?

When Cisco Extension Mobility is implemented, which CSS is used for calling privileges?

A.
The user device profile line CSS combined with the device CSS of the physical phone used to log in the extension mobility user.

B.
The user device profile device CSS combined with the line CSS of the physical phone used to log in the extension mobility user.

C.
Only the user device profile device CSS is used

D.
The combined line/device CSS of the physical phone is used to log in the extension mobility user.

E.
The combined line/device CSS of the user device profile.

Explanation:
Ok, check the Note section 4-56: Cisco Extension Mobility and CSSs

Cisco Extension Mobility does not modify the device CSS.
Cisco Extension Mobility modifies the line CSS:
– When using the line/device CSS approach (recommended for CoS implementation):
Line CSS of user device profile is applied; CoS settings of the user are enforced.
Device CSS is not modified; local gateway selection is allowed, depending on used device (at any location).

If only device CSSs are used, the CSS is not updated, and no user-specific privileges can be applied. The user inherits the privileges that are configured at the device that is used for logging in.