In: Economics
An externality is present in a free market whenever:
a.firms hire employees from outside the firm to fill positions normally filled by promotion from within the firm.
b.a monopolist spends funds to keep potential competitors out of the market.
c.an activity generates costs or benefits that are not reflected in market prices.
d.a tax is imposed on the supplier of a good.
Option
c.an activity generates costs or benefits that are not reflected in market prices.
An externality is a cost or benefits from a transition to the third party which is not in the transaction. A cost is incurred by negative externality and a benefit from positive externality.