Annabelle has 56 1-centimeter cubes. What are the dimensions of a rectangular prism Annabelle could build with all the cubes?
a. 7 units long, 4 units high, 2 units wide
b. 6 units long, 5 units high, 5 units wide
c. 10 units long, 2 units high, 3 units wide
d. 8 units long, 2 units high, 4 units wide