Detailed Instructions: You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.
Problem:Beavers build their homes in ponds and streams. Which characteristic is least critical to building homes in an aquatic environment?
(A) waterproof fur (B) webbed hind feet (C) large, sharp teeth (D) flat, wide tail
Solution:
C