Jesse cuts a circular paper disk of radius 12 along two radii to form two sectors, the smaller having a central angle of 120 degrees. He makes two circular cones, using each sector to form the lateral surface of a cone. What is the ratio of the volume of the smaller cone to that of the larger?
Answer Choices
A. \dfrac{1}{8}
B. \dfrac{1}{4}
C. \dfrac{\sqrt{10}}{10}
D. \dfrac{\sqrt{5}}{6}
E. \dfrac{\sqrt{10}}{5}