2010 Pascal Problem 4

One of the following 8 figures is randomly chosen. What is the probability that the chosen figure is a triangle?

\textbf{(A)}\ \frac{3}{8}\quad \textbf{(B)}\ \frac{3}{4}\quad \textbf{(C)}\ \frac{1}{8}\quad \textbf{(D)}\ \frac{1}{2}\quad \textbf{(E)}\ \frac{1}{3}

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.