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.

Category: ORATORY 
Clue: "How can the 'consent of the governed' be given," she asked in 1873, "If the right to vote be denied?"
susan b. anthony

Category: TRANSPORTATION 
Clue: An aircraft that can take off & touch down on water or land is called this, like a class of animals
amphibious

Category: EXPLORING AFRICA 
Clue: John Hanning Speke accompanied him twice on explorations into Africa's interior, reaching Lake Tanganyika

sir richard burton