You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.
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Question: Category: CAPITAL CITIES 
Clue: Home to the oldest cathedral & the oldest university in the Americas, this capital was founded in 1496

Answer: santo domingo


Question: Category: LANDMARKS 
Clue: In the 1879 Mathew Brady photo seen here, this structure was about 150 feet tall

Answer: washington monument


Question: Category: AFRICAN CITIES 
Clue: Africa's most populous city not on a navigable body of water; its settlers didn't need water when they had gold

Answer:
johannesburg