Which statement best describes the concept of the double taxation of corporation income?

a. Subject to two levels of taxation: regular tax and the alternative minimum tax

b. Corporate income is taxed twice at the corporate level: first when earned and than a second time of appreciated property is distributed to shareholder

c. Corporate income is taxed when a earned by a C corporation and than a second time at the shareholder level when distributed as a dividend

d. Corporate income is subject to two levels of taxation: at the federal level and a second time at the state level