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]: The shape of a riverbed changes over time as a result of which gradual process?  
 (A) erosion (B) dissolving (C) plate shifting (D) compaction
[A]: A


[Q]: Which describes a specific characteristic necessary for survival in the desert?  
 (A) conserving water (B) hiding from predators (C) hibernating for long periods (D) producing many offspring
[A]: A


[Q]: Chris stirs a cup of hot chocolate. He uses a wooden stick thinking it will stay cooler than a metal spoon. Which activity best describes the student's action?  
 (A) comparing data (B) asking a question (C) making a prediction (D) forming a conclusion
[A]:
C