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]: Molly was making iced tea by putting tea bags in boiling water. She needed to cool the hot tea quickly, so she poured it into a pitcher full of ice. Which best describes the flow of thermal energy?
(A) from the ice to the tea (B) from the tea to the ice (C) from the pitcher to the tea (D) from the ice to the pitcher
[A]: B

[Q]: Researchers recently discovered a gene in humans that previously was unknown to science. Which statement best explains why the gene probably was not discovered much sooner?
(A) The gene only recently evolved in humans. (B) The technology used to study genes is still being developed. (C) Scientists were not interested in genes until a few years ago. (D) Scientists were sure they had already discovered every possible gene.
[A]: B

[Q]: Tyrone put two stones in a plastic bottle of water and shook it. After he stopped shaking the bottle, he observed that small pieces of the stones were floating in the water. What is the best prediction he can make based on this observation? If shaking the bottle causes pieces of stones to break off,
(A) then using cold water will break off more pieces. (B) then using hot water will make the stones change colors. (C) then shaking for a longer amount of time will break off more pieces. (D) then shaking for a shorter amount of time will make the rocks change colors.
[A]:
C