5. (Figure: Traffic Lights in Plymouth) Look at the figure Traffic Lights in Plymouth. Plymouth has 1,000 residents. Each of the residents has the same individual marginal benefit per traffic light. If the town's population doubles and the new residents share the identical individual marginal benefit of the existing residents, the socially efficient quantity of traffic lights will:A) rise. B) stay the same. C) fall to zero. D) fall.

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