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.

Input: Consider Input: Which of these is an environmental benefit of converting to solar energy?  
 (A) a decrease in air pollution (B) an increase in the cost of energy (C) an increase in the use of fossil fuels (D) a decrease in electrical energy production

Output: A


Input: Consider Input: Which of the following has the least momentum?  
 (A) a 0.5 kg mass with a 1000 m/s velocity (B) a 1 kg mass with a 100 m/s velocity (C) a 10 kg mass with an 11 m/s velocity (D) a 100 kg mass with a 2 m/s velocity

Output: B


Input: Consider Input: Which tool would be the most helpful in an investigation of the life cycle of a monarch butterfly?  
 (A) a sharp knife (B) a magnifying glass (C) a long piece of string (D) a large jar with air holes in the top


Output: D