The Following Data Has Been Collected About Keller Company's Stockholders

The following data has been collected about Keller Company's stockholders' equity accounts: $\begin{array}{|l|l|}\hline \text { Common stock } \$ 10 \text { par value } 20,000 \text { shares authorized and } 10,000\\\text { shares issued, } 9,000 \text { shares outstanding }&\$100,000\\\hline \text { Paid-in capital in excess of par value, common stock } & 50,000 \\\hline \text { Retained earnings } & 25,000 \\\hline \text { Treasury stock } & 11,500 \\\hline\end{array}$ Assuming the treasury shares were all purchased at the same price, the number of shares of treasury stock is:

A) 1,150.
B) 1,000.
C) 575.
D) 11,000.
E) 21,000.