On December 31, Mercury Corporation has the following data available: Net Income $200,000 Interest expense 20,000 Preferred dividends 20,000 Total assets at the beginning of the year 850,000 Total assets at the end of the year 780,000 Total common stockholders' equity at the beginning of the year 550,000 Total common stockholders' equity at the end of the year 490,000 What is return on common equity?

A 42.31%

B 38.46%

C 22.09%

D 34.62%