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 consistency, answers should be in all lower cased letters.

[Q]: Category: BUSINESS & INDUSTRY 
Clue: This stagecoach company owned the Pony Express during the last few months of its existence
[A]: wells fargo


[Q]: Category: SEX CHANGES 
Clue: Don't let the pearls fool you, these lady bivalves can change into males when it suits them
[A]: oysters


[Q]: Category: ZACHARY TAYLOR 
Clue: After this now defunct party nominated Taylor, it sent him a letter postage due, which he refused
[A]:
whig