What Is the Core Argument in the Concept "Tragedy of the Commons

What is the core argument in the concept "tragedy of the commons"?

A) Monetary systems are often manipulated by elites.
B) Governments will intervene when it is in their direct interest to do so.
C) Resources that are shared among several groups are ruined by individual actions.
D) Overpopulation is the result of lack of family planning methods.
E) Famine is likely to result after an isolated area experiences crop failure.