1965 AHSME Problem 20

For every n the sum of n terms of an arithmetic progression is 2n + 3n^2. The rth term is:

\textbf{(A)}\ 3r^2 \qquad \textbf{(B) }\ 3r^2 + 2r \qquad \textbf{(C) }\ 6r - 1 \qquad \textbf{(D) }\ 5r + 5 \qquad \textbf{(E) }\ 6r+2\qquad

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