Choice "C" is correct. The statement of activities is most similar to an income statement. The not-for-profit organization's statement of activity shows revenues, expenses and changes in net assets (net income).
Choice "b" is incorrect. The statement of financial position for not-for-profits is the closest to a balance sheet. The statement shows assets, liabilities and net assets (equity).
Choice "d" is incorrect. The statement of cash flows for not-for-profits is generally the same as the statement of cash flows in commercial settings.
Choice "a" is incorrect. The statement of retained earnings does not have a correlating stand-alone financial statement in not-for-profit settings. Although the statement of activities shows changes in each classification of net assets, there is no statement exclusively devoted to equity transactions.