What is the primary purpose of a 'rebuttal' in an argumentative essay concerning cyber issues?
A) To introduce new evidence supporting the main claim.
B) To summarize the entire essay's arguments and conclusion.
C) To acknowledge and address opposing viewpoints, demonstrating why they are flawed or less significant than the main argument.
D) To present a personal opinion without factual support.
E) To provide background information about the cyber issue being discussed.