Consider an Industry Producing Good X

Consider an industry producing good X.The quantity of good X produced in a competitive free market will be greater than the socially optimal level if

A) the production of good X generates a positive externality.
B) the consumption of good X generates a positive externality.
C) the production of good X generates a negative externality.
D) the government has imposed a tax on the production of good X.
E) good X is a public good.