Concept:The Third Republic in Nigeria operated under a two-party system enforced by the government.Explanation:The regime of General Ibrahim Babangida designed a two-party structure for the Third Republic.The two recognised parties were the National Republican Convention (NRC) and the Social Democratic Party (SDP).These parties were deliberately created to draw support from a national, rather than regional or tribal, basis.This arrangement was intended to reduce ethnic and regional divisions in politics.Answer:A. Two-party