An ice cream store sells two different sizes of ice cream cones. The first cone is 4 inches tall and has a 1-inch radius. The second cone is 6 inches tall and has a 1.5-inch radius. What is the ratio of the volume of the smaller cone to the volume of the larger cone?

A.
4 : 9

B.
8 : 27

C.
9 : 4

D.
27 : 8