Cisco Exam Questions

what summary address would be sent from router A?

Refer to the exhibit.

In this VLSM addressing scheme, what summary address would be sent from router A?

A.
172.16.0.0 /16

B.
172.16.0.0 /20

C.
172.16.0.0 /24

D.
172.32.0.0 /16

E.
172.32.0.0 /17

F.
172.64.0.0 /16

Explanation:

Router A receives 3 subnets: 172.16.64.0/18, 172.16.32.0/24 and 172.16.128.0/18.
All these 3 subnets have the same form of 172.16.x.x so our summarized subnet must be
also in that form -> Only A, B or .
The smallest subnet mask of these 3 subnets is /18 so our summarized subnet must also
have its subnet mask equal or smaller than /18.
-> Only answer A has these 2 conditions -> .