You are given a science question (hard-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 pot is touching the flame of a gas stove, and the substance in the pot is heating up due to the contact. This is an example of which type of energy transfer?  
 (A) radiation (B) convection (C) conduction (D) vaporization
[A]: C


[Q]: Water freezing is an example of a  
 (A) liquid changing to a solid (B) solid changing to a liquid (C) gas changing to a solid (D) gas changing to a liquid
[A]: A


[Q]: Why are rapidly occurring environmental changes more likely to cause extinctions than slowly occurring changes?  
 (A) Slow changes allow time for adaptation. (B) Rapid changes require little adaptation. (C) Slow changes affect only small regions. (D) Rapid changes have a global effect.
[A]:
A