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: Alan is using cabbage juice to determine the relative pH of various household solutions. Which of these steps communicates the results of his investigation?
(A) Conduct multiple trials (B) Write down a procedure (C) Identify the materials to be tested (D) Record observations and data in a journal

A: D
****
Q: As part of a study, a scientist observed a number of different molecular changes in matter. Which of the following observations provides evidence of a physical change?
(A) using heat to burn a log in a fireplace (B) using light to produce sugar in plants (C) a cake that was baked from many ingredients (D) a bottle that was broken into many small pieces

A: D
****
Q: When you have too little water in your body, your kidneys excrete antidiuretic hormone (ADH). What happens in response to ADH?
(A) You get thirsty and urinate more. (B) You get thirsty and urinate less. (C) You get hungry and sweat more. (D) You get hungry and sweat less.

A:
B
****