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.

Some people carry a mutated allele of a particular gene that makes them resistant to HIV infection and AIDS. Which best describes this type of mutation?  
 (A) beneficial (B) asexual (C) harmful (D) unicellular
A

What tool would be used to examine a fingerprint?  
 (A) a graduated cylinder (B) a hand lens (C) a pair of goggles (D) a thermometer
B

In your body, what two organs work together to make sure that oxygen gets to all the other organs of your body?  
 (A) Lungs and kidneys (B) Heart and lungs (C) Brain and kidneys (D) Heart and liver

B