Due to Externalities Generated by Home Landscaping, Its Price

Multiple Choice

Due to externalities generated by home landscaping, its price:

A) is above the optimal level, and quantity traded is below the optimal level.
B) is below the optimal level, and quantity traded is above the optimal level.
C) and quantity traded are both above the optimal level.
D) and quantity traded are both below the optimal level.
E) must fall in order for the market to reach equilibrium.