When attempting to modify a child's behavior using negative reinforcement,

the desired result is that the child
will:

A. Withdraw from certain social
activities

B. repeat behavior for which they
get the desired result

C. avoid behaviors that carry
undesireable consequences

I am thinking (C) is the correct answer,
can you please help?

Read

http://www.vtaide.com/png/rewards.htm

I think you are right, but read to be sure.

The "desired" result can only be C. If you desired the other two chioces, A would make you a psychological torturer and, B is an answer to positive reinforcement outcome and, is inaplicable.