P_a and P_b Represent the Prices That Citizens (A)and (B),the

P_a and P_b represent the prices that citizens (a) and (b) ,the only two people in this nation,are willing to pay for additional units of a quantity (Q_c) of the public good.Q_s represents the quantity of the public good supplied by government at each of the collective prices.
-Refer to the above information.If the collective willingness to pay for an additional unit of this public good is $6,then the collective quantity demanded will be

A) one unit and the socially optimal quantity supplied will be five units.
B) two units and the socially optimal quantity supplied will be four units.
C) three units and the socially optimal quantity supplied will be three units.
D) four units and the socially optimal quantity supplied will be two units.
E) five units and the socially optimal quantity supplied will be one unit.