Choice "C" is correct. Restrictions on retained earnings are for contractual or legal appropriation of retained earnings. The purpose is to restrict dividends, and such restrictions should be disclosed in the financial statements.
Choice "a" is incorrect. Restrictions on retained earnings have no effect on the existence of retained earnings.
Choice "d" is incorrect. Completeness refers to the inclusion of all transactions and balances. Restrictions on retained earnings will not affect completeness.
Choice "b" is incorrect. Assertions about valuation and allocation deal with whether assets, liabilities, and equity interests have been included in the financial statements at appropriate amounts. Restrictions on retained earnings do not affect valuation and allocation.