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.

[Q]: Marta studied different forms of energy. Which two types of energy travel in waves?  
 (A) light and sound (B) electrical and sound (C) chemical and light (D) chemical and electrical
[A]: A


[Q]: In the morning, students observed puddles of water all over the playground. What would best explain why the playground was dry in the afternoon?  
 (A) Animals drank the water. (B) The wind stopped blowing. (C) Someone dried the puddles. (D) The water evaporated during the day.
[A]: D


[Q]: Which would best aid a scientist in discovering how Earth may have changed over time?  
 (A) finding the nest of a bald eagle (B) tracking the footprints of a wolf (C) analyzing the pollination of a sunflower (D) discovering a fossil of a seashell in a wooded area
[A]:
D