An Externality Is

An externality is

A) not a political problem because it is external to the political process.
B) not an economic problem because it is external to the market system.
C) a benefit or cost that accrues to someone who had nothing to do with the production or consumption of a good.
D) a pure political or economic good that is shared by the various nation-states all of which pay equally for the production and consumption of the good.