2005 Pascal Problem 19

A whole number is called *decreasing* if each digit of the number is less than the digit to its left. For example, 8540 is a decreasing four-digit number. How many decreasing numbers are there between 100 and 500?

\textbf{(A)}\ 11\quad \textbf{(B)}\ 10\quad \textbf{(C)}\ 9\quad \textbf{(D)}\ 8\quad \textbf{(E)}\ 7

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

Full credit to this problem is given to the CEMC, you may view all Pascal contests here.