Definition: You are given a question on high school microeconomics. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: Which of the following is a fundamental aspect of the free market system?
(A)A high degree of government involvement. (B)Public ownership of resources. (C)Private property. (D)Central planners set wages and prices.

C