Please provide a detailed explanation on how to find Socially Optimal Value

3839. In a small and isolated community, there are 25 consumers, each of whom has the following utility for mosquito control during the summer: U = 30X - 1.5X2 where X is the amount of mosquito control purchased in aggregate by members of the community, and U is the utility measured in dollars for each individual when X units of mosquito control are purchased (note that each individual receives benet from mosquito control, whether of not that individual buys any mosquito control). Mosquito control costs $150 per unit. Questions 38 and 39 concerns this situation. 38. The socially optimal level of mosquito control is: A) 0 B) 1 C) 2 D) 30 E) 40 F) 5 G) 6 H) 7 I) 8 J) none of the alternatives