$6.$ Zelienople Co$.$ reported the following information at December $31,2016$:

Preferred stock, $$10$ par, $5,000$ shares authorized, cumulative $ $50,000$

Common stock, $$1$ par, $500,000$ shares authorized $200,000$

Additional paid$-$in capital$$Common $25,000$

Retained earnings $75,000$

Total contributed capital and retained earnings $$350,000$

Less: Treasury stock $(400$ shares at cost$)5,000$

Total stockholders' equity $$345,000$

The number of shares of common stock issued is

a$.5,000.$

b$.200,000.$

c$.500,000.$

d$.550,000.$