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.

[Q]: Cells come in two basic types, prokaryotic and eukaryotic. Which cell structure is found in both prokaryotic and eukaryotic cells?  
 (A) vacuole (B) nucleoid (C) mitochondrion (D) cytoplasm
[A]: D


[Q]: Which is the most important safety measure to follow when using an acid in a classroom laboratory?  
 (A) wearing protective clothing and goggles (B) keeping the window open (C) closing the door to the hall (D) using bright fluorescent lights
[A]: A


[Q]: Two identical books are on opposite ends of a table. Which of these would increase the gravitational force exerted between the two books?  
 (A) decrease the distance between the books (B) decrease the mass of the books (C) decrease the mass of the table (D) decrease the temperature in the room
[A]:
A