In which sentence does the verb agree with the subject?

a. noisily, four quarters fall to the floor.
b. five dollars are the cost of the blueberries.
c. three weeks are too much time for such a simple assignment.

The correct answer would be option A. The sentence wherein the verb agrees with the subject is: Noisily, four quarters fall to the floor. The subject is four quarters which is plural form, therefore, the verb should also be in plural which is "fall".