What is the minimum number of SIP dial peers required?

You are CCNA VOICE associate in Certkey.com. You need to configure a Cisco Unity Express system with a voicemail pilot number of 1900, an AutoAttendant with pilot number of 2900, and an Administration via Telephone pilot number of 3900. What is the minimum number of SIP dial peers required?

A.
0

B.
1

C.
2

D.
3