Which of the following statements about UCM default phone button templates is not true?

A.
You cannot modify the button assignments within them.

B.
You can copy them and rename the copies to customize them.

C.
You cannot delete them.

D.
You can rename them, but doing so will automatically unassign them.

Explanation:
You cannot rename Cisco Unified Communications Manager (UCM) default phone button templates. However,
you can rename custom phone button templates. Renaming an in-use custom phone button template will not
break the relationship between that template and its assigned phones. Each phone that has been assigned to
that custom template will use that template under its new name.
A phone button template is a UCM feature that enables the application of a configuration for many phones
within an organization without configuring each phone individually. Cisco IP phones have standard, or default,
phone button templates that can be applied to configure phones with default button settings. The standard
phone button template that can be applied to a given IP phone depends on the model of the IP phone.
You cannot modify the button assignments within default phone button templates. However, you can copy
default phone button templates and rename the copies to customize them. It is possible to reassign the buttons
on an IP phone to functions that differ from the standard phone button template that was originally applied to
the phone. Although you cannot modify the buttons on a default phone button template, you can copy the
default template and rename the copy, which enables you to base a custom phone button template on a default
template.
You cannot delete default phone button templates, even if the default template is not assigned to a phone. You
can delete custom phone button templates as long as the custom template is not assigned to any phones and
is not the only template for the given model of IP phone.

Cisco: Cisco Unified IP Phones: Phone Button Templates