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 light year is used to measure  
 (A) time. (B) distance. (C) luminosity. (D) temperature.

SOLUTION: B

PROBLEM: A cut to the skin is treated with antiseptic first to avoid  
 (A) an immune response. (B) a bacterial infection. (C) bruising of tissues. (D) an allergic reaction.

SOLUTION: B

PROBLEM: A shiny aluminum screen can be placed on the windshield of a parked car. This screen helps to keep the car cool because it  
 (A) reflects the sunlight (B) absorbs heat (C) causes evaporation (D) conducts electricity

SOLUTION:
A