The numbers 1 through 20 are written on twenty golf balls, with one number on each ball. The golf balls are placed in a box, and one ball is drawn at random. If each ball is equally likely to be drawn, what is the probability that the number on the golf ball drawn is a multiple of 3?
Answer Choices
A. \frac{3}{20}
B. \frac{6}{20}
C. \frac{10}{20}
D. \frac{5}{20}
E. \frac{1}{20}