Lots of different answers...interesting...
Well.
Correct answer is actually 'C'.
It's pronounced "N-ee-k-o" like just d3 said.
BUT, the 'o' isn't a long 'o' like "Oh my!". BUT, it's a short o, just like when you say "Awwe", but with an O, not an A.
Anyways, thanks for playing..err.....uhh..ahem..."The.....Guess How You Pronounce a Name...Game..." Yea......Pro name right there