2001 Cayley Problem 18

How many five-digit positive integers, divisible by 9, can be written using only the digits 3 and 6?

\textbf{(A)}\ 5\quad \textbf{(B)}\ 2\quad \textbf{(C)}\ 12\quad \textbf{(D)}\ 10\quad \textbf{(E)}\ 8

If there are no answer choices shown, enter a numerical answer.

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