51. The volume of a right circular cone with radius r and height h is , where r and h have the same unit of measure. Cones A and B are both right circular cones. The radius of Cone B is 2 times the radius of Cone A. Cone B’s height is Cone A’s height. Compared to the volume of Cone A, the volume of Cone B is:

B. as great.

C. as great.