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 Q]: Which of the following is most likely to disrupt the natural balance in an ecosystem?  
 (A) introduction of a non-native species (B) reduced daylight hours during winter (C) preventing the cutting of trees in forests (D) riverbank erosion resulting from springtime flooding
[EX A]: A

[EX Q]: When the cardboard cone of a radio speaker vibrates, it produces a sound in the air around it. The cone produces this sound by transferring which of the following to the air around it?  
 (A) heat (B) current (C) wave motion (D) magnetic force
[EX A]: C

[EX Q]: One example of a trait passed from a parent plant to its offspring is ___.  
 (A) the amount of water in the plant's environment (B) the amount of sunlight shining on the plant (C) the color of the flowers on the plant (D) the nutrients in the soil where the plant grows
[EX A]:
C