You want to allow IP Phones in subnet 10.100.1.0 to register with Cisco Unified Communications Manager Express at address 10.10.1.1. Which two commands should you use?
A.
ip helper address 10.10.1.1 under interface FastEthernet0/0.100
B.
option 150 ip 10.10.1.1 under dhcp pool Phones
C.
default-router 10.100.1.1 under dhcp pool Phones
D.
subnet prefix-length 24 under dhcp pool Phones