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]: What type of galaxy is the Milky Way?  
 (A) spiral (B) elliptical (C) irregular (D) oval
[A]: A


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


[Q]: If a scientist wants the medical community to revise old information and use new research findings in the treatment of a disease, it would be best to present the information  
 (A) at a school science fair. (B) in a newspaper article. (C) at a physicians' conference. (D) in a television commercial.
[A]:
C