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.

[EX Q]: Which of these reduces the need for people to use nonrenewable resources?
(A) recycling paper products (B) watering the lawn once a week (C) designing cars that are fuel efficient (D) using coal to generate electricity
[EX A]: C

[EX Q]: Which is a hypothesis that can be easily tested?
(A) The Moon causes high tides. (B) During which season are the tides the highest? (C) What is the phase of the Moon when tides are highest? (D) When the Moon is full, the tides will be at their highest.
[EX A]: D

[EX Q]: Tobacco has been linked to many health problems. What is the most complete list of forms of tobacco that cause cancer?
(A) cigarettes and snuff (B) chewing tobacco and snuff (C) cigarettes and chewing tobacco (D) cigarettes, chewing tobacco, and snuff
[EX A]:
D