During the summer, Mark works on his uncle's horse farm. One of Mark's many chores is to load bales of hay onto a wagon and haul them from the field into the barn. The proportional relationship between the number of wagon loads, x, and the number of bales of hay Mark can haul, y, can be modeled by the equation y = 12x.

If Mark hauled 60 bales of hay to the barn, how many wagon loads did it take?

A) 4
B) 4 1/2
C) 5
D) 5 1/2