Which pairs is not correctly matched?

Option 3 is not correctly matched. Belmopan is the capital of Belize, not Nicaragua, as shown in lists of North American/Central American capitals where Belize is paired with Belmopan and Bahamas with Nassau, Costa Rica with San José, and the Dominican Republic with Santo Domingo. Authoritative regional capital lists also record Nicaragua’s capital as Managua, confirming that Belmopan does not belong to Nicaragua. Therefore the pair “Nicaragua — Belmopan” is incorrect, while the other three pairs (Bahamas — Nassau; Costa Rica — San José; Dominican Republic — Santo Domingo) are correctly matched according to the cited capital lists.