Concept:One-party system concentrates all political power in a single ruling party.Explanation:In a one-party system, opposition parties are not allowed to exist.The ruling party controls all government institutions and organs of state power.There is no legal channel for citizens to challenge government decisions.This lack of opposition and unchecked power often encourages authoritarian or dictatorial rule.Thus, the system tends to end in dictatorship rather than democracy, fair electoral contest, or freedom of expression.Answer:B. dictatorship