Points B and C lie on \overline{A D}. The length of \overline{A B} is 4 times the length of \overline{B D}, and the length of \overline{A C} is 9 times the length of \overline{C D}. The length of \overline{B C} is what fraction of the length of \overline{A D} ?
Answer Choices
A. \dfrac{1}{36}
B. \dfrac{1}{13}
C. \dfrac{1}{10}
D. \dfrac{5}{36}
E. \dfrac{1}{5}