farmer brown sprays insecticides on his crops to kill insects. several days after spraying, he notices many…

farmer brown sprays insecticides on his crops to kill insects. several days after spraying, he notices many dead bugs around the pond. that summer, the number of frogs around the pond was lower than ever. the frog population has declined because\na the chemical killed the frogs.\nb farmer brown scared the frogs away.\nc bugs are the limiting factor for the frogs.\nd the chemical spray is a limiting factor for the bugs.
Answer
Brief Explanations:
Frogs often eat bugs. When the insecticide kills bugs, the food - source of frogs is reduced. Bugs being the limiting factor for frogs can cause the frog population to decline. There's no indication the chemical directly killed frogs, and there's no mention of Farmer Brown scaring frogs away. The question is about the frog population decline, not just the bug - limiting factor.
Answer:
C. bugs are the limiting factor for the frogs.