1950 AHSME Problem 17

The formula which expresses the relationship between x and y as shown in the accompanying table is:

\begin{array}{|c|c|c|c|c|c|} x&0&1&2&3&4\\ y&100&90&70&40&0\\ \end{array}

\begin{array}{l} \textbf{(A)}\ y=100-10x\qquad\textbf{(B)}\ y=100-5x^{2}\qquad\textbf{(C)}\ y=100-5x-5x^{2}\qquad\\ \textbf{(D)}\ y=20-x-x^{2}\qquad\textbf{(E)}\ \text{None of these} \end{array}

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.