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 student has just completed a laboratory activity. What is the last action that the student should perform before leaving the lab area?  
 (A) wash hands (B) turn off all equipment (C) put away all glassware (D) wash instruments and table tops

SOLUTION: A

PROBLEM: A student plans to grow algal colonies in solutions with different concentrations of liquid fertilizer. Which is a clear and testable hypothesis to guide this investigation?  
 (A) Algae like fertilizer. (B) Fertilizer is good for algae. (C) Fertilizer improves the genetic traits of algae. (D) Algal growth rate increases with fertilizer concentration.

SOLUTION: D

PROBLEM: Over a two-week period, several students complain of feeling sick. Their symptoms include a cough, fever, and a sore throat. What describes the most likely cause of these symptoms?  
 (A) exposure to hot weather (B) decrease in physical exercise (C) consumption of bad food (D) infection by a virus

SOLUTION:
D