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: GENERAL ED. 
Clue: A zygote is produced by the union of 2 of these sex cells, an egg & a sperm
gametes

Category: SHAKE, RATTLE & ROLL 
Clue: The Banzai Pipeline rolls in as part of the venue for the Vans Triple Crown of this sport
surfing

Category: MADAM, I'M ADAM SMITH 
Clue: Folks never seem to remember, but my masterwork is actually titled "An Inquiry into the Nature and Causes of" this

the wealth of nations