Answer:
I think the answer is A.
Explanation:
Choice B is wrong because the paragraph is not based on snakes eating other animals.
Choice C is wrong because they are not only talking about snake's venom used for medicine.
Choice D is wrong because it is not only talking about poisonous snakes.
I hope this is correct.
"Neutral"..? Not sure. Or maybe "open"?
I think it is single but i'm not sure