Please answer the following question: Fact 1: Harming an animal species has a negative impact on the population size of that species. Fact 2: Animals are harmed because of cosmetic testing. Given the two facts above, answer the question "What has a negative impact on the population size of a species?" with the following options: - Pesticides - influenza - steroids - liver cancer - cloudy and rainy weather - massive damage - cosmetic testing - killing insects
A:
cosmetic testing