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.

Ex Input:
Which is the best example of evaporation?  
 (A) raindrops freezing (B) an ice cube melting (C) a puddle drying in the sun (D) a sponge soaking up water

Ex Output:
C


Ex Input:
Kim lost her hammer outside. When she found it a few months later, some parts of the metal were covered with flaky, brown rust. Which type of change occurred when rust formed on the hammer?  
 (A) chemical (B) electrical (C) thermal (D) physical

Ex Output:
A


Ex Input:
Which technology used to generate electrical power involves a trade-off between economical electricity and long-term waste disposal problems?  
 (A) fossil fuel (B) nuclear reactor (C) solar collector (D) wind turbine

Ex Output:

B