Refer to the exhibit.
What is the most efficient summarization that R1 can use to advertise its networks to R2?
A.
172.1.4.0/25
172.1.4.128/25
172.1.5.0/24
172.1.6.0/24
172.1.7.0/24
B.
172.1.0.0/22
C.
172.1.4.0/24
172.1.5.0/24
172.1.6.0/24
172.1.7.0/24
D.
172.1.0.0/21
E.
172.1.4.0/22
Explanation:
When the subnet mask is /22, R1 can advertise its networks to R2.