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]: A student conducts an investigation. In order to make a valid conclusion, she must  
 (A) have a testable hypothesis. (B) place the data in a graph. (C) use the best technology. (D) test multiple variables.
[A]: A


[Q]: Which occurs as a result of Earth's tilt on its rotating axis?  
 (A) movement of the tides (B) prevalent or trade winds (C) seasonal changes in the climate (D) light and dark changes of day and night
[A]: C


[Q]: A certain type of hybrid car utilizes a braking system in which energy is recovered and stored in batteries. This is an example of which type of energy conversion?  
 (A) kinetic energy converted to potential energy (B) chemical energy converted to kinetic energy (C) chemical energy converted to thermal energy (D) thermal energy converted to potential energy
[A]:
A