Which change must be made to resolve this issue?

Refer to the exhibit.

An engineer sets up a DMVPN connection to connect branch 1 and branch 2 to HQ branch 1 and branch 2 cannot communicate with each other.

Which change must be made to resolve this issue?
A . R1(config)#int e1/1
R1(config-if)#no ip split-horizon eigrp 100
B . R1(config)#int tunnel1
R1(config-if)#no ip split-horizon eigrp 100
C . R1(config)#router eigrp 100
R1(config-if)#neighbor 172.16.1.3
D . R1(config)#router eigrp 100
R1(config-if)#neighbor 172.16.1.2

Answer: B