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]: Martin is writing a report for science class about how the tilt of Earth affects living organisms. Which subject should Martin include in his report that is directly affected by Earth's tilt?  
 (A) night and day (B) cloud formation (C) phases of the Moon (D) changing of the seasons
[A]: D


[Q]: Compost piles have many parts, such as leaves, moisture, vegetables, and microorganisms. Which part of a compost pile breaks down materials and adds nutrients to the soil?  
 (A) leaves (B) moisture (C) vegetables (D) microorganisms
[A]: D


[Q]: One year a farmer decided not to plant crops in one of his fields. During that year his farm received a greater amount of precipitation than normal. Which will most likely occur in that unplanted field as a result of the greater precipitation?  
 (A) more carbon dioxide will be trapped in the field (B) erosion of topsoil will increase in the field (C) invasive species will inhabit the field (D) animals will dig burrows in the field
[A]:
B