A: Homeostasis
Reason: cell membrane has nothing to do with question and C and D are terms for sugars
The correct answer is A. Variation.
The key word in the text is "different." There is a variety of horn sizes among horned animals.
Eliminated Answer Choices:
The answer cannot be B. Overproduction because the text does not give any information about reproducing or populations.
The answer cannot be C. Survival of fit individuals because survival of the fit is related to adaptations and the text does not mention anything about that.
Hope this helps. Good luck! :)
