Which three steps must be completed in order to assign a service URL to an IP Phone button? (Choose three.)
A.
Add an IP phone service.
B.
Assign the IP phone service partition to the CSS of the phone.
C.
Create a phone button template that includes a service URL and assign it to the phone.
D.
Create a softkey template that includes a service URL and assign it to the phone.
E.
Subscribe the phone to the service.
F.
Associate a valid user profile with the phone.