Tara Had Originally Created a /28 Mask for the 12

Multiple Choice

Tara had originally created a /28 mask for the 12 servers in the sales group server pool. However, her company has just merged with a competitor and she needs to expand the subnet to accommodate another 20 servers. Which of the following new subnet masks will accommodate the new servers in addition to the original servers while having the fewest number of unused IP addresses remaining?

A) /29
B) /27
C) /26
D) /25