The frequency of JEB-2 carriers in the American Saddlebred horse is approximately 3%. Assuming that there are 18,000 Saddlebred foals born each year in the US, and that in theory the parents of these foals are unrelated and are selected at random for mating, how many Saddlebred foals born each year in the US are expected to be JEB-2 carriers?
a) 540
b) 600
c) 648
d) 540