Fact 1: Harming an animal species has a negative impact on the population size of that species. Fact 2: Some species of amoeba are harmful parasites. Given the two facts above, what can negatively impact a species?

Choose your answer from:
[A]. chemicals;
[B]. elephant;
[C]. cells;
[D]. dog;
[E]. drought;
[F]. mines;
[G]. steroids;
[H]. amoeba;
Answer:
[H].