What Does Double Taxation Mean

What does double taxation mean?

A) Companies must pay taxes on their income, and then employees must pay taxes on their salaries and wages.
B) Companies have to pay both sales taxes and income taxes.
C) Companies must pay taxes on their earnings, and then stockholders pay taxes on their dividends.
D) Suppliers tax their customers, and in turn these businesses tax the ultimate consumer.
E) Companies must pay taxes on corporate income and then additional taxes on distributions to profit stockholders.