as a behavioral adaptation as a survival disadvantage as a response to a stimulus as an acquired characteristic
I gave my students this multiple choice question: The bacterium Brucella abortus causes fever in humans. Biologists studying this bacterium found that when exposed to light, the bacterium becomes more virulent. How can this change in virulence most likely be described?

Only one answer is correct among these 4 choices:
- as a behavioral adaptation
- as a survival disadvantage
- as a response to a stimulus
- as an acquired characteristic

Could you tell me which one is correct?

as a response to a stimulus