TASK DEFINITION: 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.
PROBLEM: Which of these is a structure that is present in all organisms?  
 (A) a tissue (B) a cell (C) a stomach (D) a brain

SOLUTION: B

PROBLEM: Which would be the best method to use to dispose of cardboard boxes not utilized by a local grocery store?  
 (A) burn them once a month (B) send them to be dumped in a remote area (C) have them recycled for future paper products (D) put them into a dumpster with the rest of the trash

SOLUTION: C

PROBLEM: When air is heated, it will most likely  
 (A) expand and fall. (B) expand and rise. (C) condense and fall. (D) condense and rise.

SOLUTION:
B