Question

Which of the following is an example of onomatopoeia?
A) running
B) drink
C) buzz
D) girl

Answer 1

Buzz is an example of onomatopoeia

Answer 2

A word or a combination of words, whose sound seems to resemble the sound it denotes (for example: "hiss", "buzz", "etc.) is called onomatopoeia.  

Example sentence: Her heels clacked on the hardwood floor.

So, keeping the definition of onomatopoeia in mind it can be said option C) buzz is onomatopoeia.