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.
--------
Question: Category: GOAT-POURRI 
Clue: Goat Island splits Niagara Falls into the American Falls & this waterfall on the Canadian side

Answer: horseshoe falls


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

Answer: amphibious


Question: Category: THE BEATLES 
Clue: John Lennon said this 1965 movie title tune was one of his favorites, in part because he wrote it about himself

Answer:
"help!"