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.

Input: Consider Input: Which statement correctly describes a relationship between two human body systems?  
 (A) The digestive system absorbs nutrients which are transported by the nervous system. (B) The digestive system absorbs nutrients which are transported by the circulatory system. (C) The circulatory system exchanges gases which are transported by the nervous system. (D) The circulatory system exchanges gases which are transported by the digestive system.

Output: B


Input: Consider Input: As water cools to a temperature of zero degrees Celsius and forms ice, water molecules tend to  
 (A) move farther apart. (B) vibrate rapidly. (C) flow more randomly. (D) gradually expand.

Output: A


Input: Consider Input: Which part of the body works closely with the digestive system to transport nutrients to the cells?  
 (A) lungs (B) blood (C) kidneys (D) esophagus


Output: B