25. The demand curve for fire extinguishers slopes downward and the supply curve for fire extinguishers slopes upward. The consumption of the 750th fire extinguisher is associated with a private cost of $25, an external cost of $0, a private benefit of $22, and an external benefit of $7. Is the socially optimal quantity of fire extinguishers less than, equal to, or greater than 750? A. The optimal quantity of fire extinguishers is less than 750. B. The optimal quantity of fire extinguishers is equal to 750. C. The optimal quantity of fire extinguishers is greater than 750. D. There isn't enough information to say with certainty