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.
--------
Question: 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

Answer: A

Question: The human immunodeficiency virus (HIV) causes AIDS. The first known human cases AIDS were in Africa in the late 1950s. Since then, tens of millions of people have died from the disease, and tens of millions more people all over the world are infected. Which term best describes the disease AIDS?
(A) isolated cases (B) outbreak (C) epidemic (D) pandemic

Answer: D

Question: The smallest particle of an element is
(A) an atom. (B) a mixture. (C) a molecule. (D) a compound.

Answer:
A