A user submits a request to add three DNs and three speed dials at the IP phone. Which component at the device level in the Cisco Unified Communications Manager accomplishes this request?

The common phone profile manages phone-wide behavioral settings such as Do Not Disturb and privacy features, but does not define line or speed dial button layout.

The common device configuration handles shared settings like softkey templates and user locale across devices, but does not control the assignment of physical line or speed dial buttons.

The phone button template directly controls how each physical button on the handset is allocated, specifying which slots are line appearances (for DNs) and which are speed dial buttons. Adding three DNs and three speed dials requires a template that reserves three line-type slots and three speed-dial-type slots matching the phone model's button capacity.

The softkey template defines on-screen softkey options during various call states such as on-hook, ringing, and connected, but has no role in assigning physical line or speed dial buttons.