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: A dish of sugar water was left on a window sill. One week later, there were only sugar crystals left in the dish. The water was gone. The best explanation for the appearance of sugar crystals is  
 (A) some of the water was absorbed by the dish. (B) the air condensed. (C) the light shining on the window sill produced more sugar. (D) the water evaporated.

SOLUTION: D

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: Eating food that is undercooked can lead to a disease that affects the digestive system. Which body part is directly affected by the disease?  
 (A) intestines (B) arteries (C) nerves (D) sinuses

SOLUTION:
A