2008 Gauss 8 Problem 16

A 4 \times 4 square grid can be entirely covered by three non-overlapping pieces made from 1 \times 1 squares. If the first two pieces are and , the third piece is

\textbf{(A)}\ [[FIG3]]\quad \textbf{(B)}\ [[FIG4]]\quad \textbf{(C)}\ [[FIG5]]\quad \textbf{(D)}\ [[FIG6]]\quad \textbf{(E)}\ [[FIG7]]

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

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