instruction:
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:
Which of the following best describes an advantage of using a mass production manufacturing system instead of a custom manufacturing system?  
 (A) Customers can provide specific feedback to workers. (B) Workers become skilled in all aspects of assembly. (C) Goods can be easily modified for customers. (D) Products can be made at a lower cost.
answer:
D


question:
Water at 20°C in an uncovered pan is evaporating very slowly. What could be done to the water to make it evaporate more quickly?  
 (A) Cover it. (B) Heat it. (C) Place it in the dark. (D) Put salt in it.
answer:
B


question:
The length of a year on Earth is a little over 365 days. The length of a year on a planet is best described as the time it takes for which to occur?  
 (A) the planet to revolve once around the Sun (B) the seasons to complete a full cycle (C) the planet to rotate once on its axis (D) the Sun to rotate once on its axis
answer:

A