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.

One example of a living thing is  
 (A) air (B) water (C) a rock (D) a worm
D

Which of these best describes a change that is physical?  
 (A) yarn being knitted into a sweater (B) the engine from a tractor being started (C) the metal on a bicycle forming rust (D) grass capturing the energy from sunlight
A

Which event occurs on a daily cycle?  
 (A) The Sun rises and sets. (B) Earth tilts on its axis. (C) Earth revolves around the Sun. (D) The Moon revolves around Earth.

A