Which subnet mask will place all hosts on Network B in the same subnet with the least amount of wasted addresses?

Refer to the exhibit.

Which subnet mask will place all hosts on Network B in the same subnet with the least amount of wasted addresses?

Exhibit:

A.
255.255.255.0

B.
255.255.254.0

C.
255.255.252.0

D.
255.255.248.0