You are given a science question (easy-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 Input:
Carlos was playing on a slide on a sunny summer day. Which property of the slide tells Carlos how much energy the slide absorbed from the Sun?  
 (A) the mass (B) the color (C) the height (D) the temperature

Ex Output:
D


Ex Input:
Which of the following is closest to the percentage of the total water on earth that is freshwater?  
 (A) 100% (B) 90% (C) 70% (D) 3%

Ex Output:
D


Ex Input:
Which of these is a structure that is present in all organisms?  
 (A) a tissue (B) a cell (C) a stomach (D) a brain

Ex Output:

B