In Public Goods Markets, the Efficient Provision of the Public

In public goods markets, the efficient provision of the public good is determined by:

A) the intersection of the horizontal sum of the demand curves of the consumers in the market with the marginal cost curve of the good.
B) the intersection of the vertical sum of the demand curves of the consumers in the market with the marginal cost curve of the good.
C) The intersection of the demand curve for each individual consumer with the marginal cost curve for the good.
D) the intersection of the total cost of producing the good and the vertical sum of the demand curves of the consumers in the market.