When a Positive Externality Exists in a Market,total Surplus

When a positive externality exists in a market,total surplus:

A) is decreased by deadweight loss compared to that same market without a negative externality.
B) is the same as a market without a negative externality.
C) is increased by deadweight gain compared to that same market without a negative externality.
D) is the same but re-distributed differently than if that same market did not have a negative externality.