2018 Cayley Problem 11

A large square has side length 4. It is divided into four identical trapezoids and a small square, as shown. The small square has side length 1. What is the area of each trapezoid?

\textbf{(A)}\ \frac{2}{3}\quad \textbf{(B)}\ 3\quad \textbf{(C)}\ \frac{9}{2}\quad \textbf{(D)}\ \frac{15}{4}\quad \textbf{(E)}\ 15

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 Cayley contests here.