Fact 1: Harming an animal species has a negative impact on the population size of that species. Fact 2: Hot weather can cause harmful bacterial growth in feeders. Given the two facts above, what can have a negative impact on a species' population size?

Possible answers: a). cigarettes. b). Pesticides. c). steroids. d). humans. e). weather. f). flooding. g). Smoking. h). viruses.
The answer is:
e).