A rectangular grazing area is to be fenced off on three sides using part of a 100 meter rock wall as the fourth side. Fence posts are to be placed every 12 meters along the fence including the two posts where the fence meets the rock wall. What is the fewest number of posts required to fence an area 36 \mathrm{~m} by 60 \mathrm{~m} ?
Answer Choices
A. 11
B. 12
C. 13
D. 14
E. 16