In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

[EX Q]: Question: Which statement best describes the Law of Superposition? Answer: In undisturbed layers of sedimentary rock, the lowest layers contain the older rocks.
[EX A]: The law of superposition is best described by: in undisturbed layers of sedimentary rock, the lowest layers contain the older rocks.

[EX Q]: Question: What play an important role in the modulation of the nuclear chain reaction? Answer: control rods
[EX A]: Control rods play an important role in the modulation of the nuclear chain reaction.

[EX Q]: Question: What is the term for the movement of molecules from an area of high concentration to an area of low concentration? Answer: diffusion
[EX A]:
Diffusion is the term for the movement of molecules from an area of high concentration to an area of low concentration.