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:
Alex looked at an electric toothbrush that had a plug with three metal prongs. Why are these prongs made out of metal?  
 (A) Metal doesn't get hot and melt when you plug it into the outlet. (B) Metal is strong and is less likely to break when you plug it into the outlet. (C) Metal is an insulator and prevents shocks when you plug it into the outlet. (D) Metal is a conductor and completes a circuit when you plug it into the outlet.

Ex Output:
D


Ex Input:
All of the planets in the solar system formed at about the same time from a large cloud of gas and dust. How is Earth different from other planets in the solar system?  
 (A) Earth has no natural satellites. (B) Earth's atmosphere is composed of gases. (C) Water is found in all three phases on Earth. (D) Volcanoes release liquid rock onto Earth's surface.

Ex Output:
C


Ex Input:
A team of surveyors takes measurements of ground altitude at horizontal intervals of 1 meter over a 400 square meter area. These measurements can best be used to produce which representation of the area?  
 (A) a topographical map (B) a map of wind currents (C) a plate tectonic diagram (D) a chart of sedimentary layers

Ex Output:

A