Which of the Following Is an Example of an Externality

Multiple Choice

Which of the following is an example of an externality that has been internalized?

A) Acid rain, originating in the United States, destroys Canadian forests.
B) Robert Frost breathes the air that has been polluted by the emissions of a nearby steel plant.
C) Erica Evans, a beekeeper, decides to keep more bees because her neighbor, an orchard owner, has agreed to compensate her for the bees' pollination of the orchard.
D) Miguel Sanchez, a concert pianist, rehearses Beethoven's "Moonlight Sonata" and his neighbors enjoy the "free concert."