instruction:
You are given a science question (hard-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:
Which of these objects is translucent?  
 (A) A student's notebook (B) A mirror on the bus (C) A brick wall of the school (D) A student's sunglass lenses
answer:
D


question:
Which is the best piece of equipment to determine the topography of the United States?  
 (A) radar (B) compass (C) satellite (D) radio
answer:
C


question:
A 72 W navigation unit on a commercial aircraft has a 24 V power supply and uses 3 A of electric current. What is the electrical resistance of the navigation unit?  
 (A) 4 ohms (B) 8 ohms (C) 13 ohms (D) 22 ohms
answer:

B