Answer:
The answer is D) in the absence of local concentrations of the flying insects on which bats feed, the bats expend much more energy on hunting for food, requiring much larger quantities of insects to sustain each bat.
Explanation:
The likely population drop after the change in streetlights would be because it would be harder for bats to find they prey, so they would need to expend more resources (energy) in doing so, and for that they would consume more insects than before.
This would likely decrease the population of insects so with less food available the city would most likely not be able to sustain the same bat population.