2002 Fermat Problem 9

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?

\textbf{(A)}\ \frac{3}{20}\quad \textbf{(B)}\ \frac{6}{20}\quad \textbf{(C)}\ \frac{10}{20}\quad \textbf{(D)}\ \frac{5}{20}\quad \textbf{(E)}\ \frac{1}{20}

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