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: Sal is looking at a map of Massachusetts. He has measured the distance, in inches, from Boston to Salem on the map. He wants to know how many actual miles the inches represent. What feature of the map should he look for?  
 (A) key (B) scale (C) legend (D) compass

Answer: B


Question: In an accurate diagram of the solar system, which object would be shown closest to Earth?  
 (A) the Moon (B) the asteroid belt (C) Mars (D) Saturn

Answer: A


Question: Which of the following can provide the human body with long-term immunity against some diseases?  
 (A) antibiotics (B) vitamins (C) vaccines (D) red blood cells

Answer:
C