Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Control rods play an important role in the modulation of the nuclear chain reaction.
What play an important role in the modulation of the nuclear chain reaction?

A theory is another name for a broad explanation that is supported by a great deal of evidence.
What is another name for a broad explanation that is supported by a great deal of evidence?

In a longitudinal wave, amplitude term is a measure of how compressed particles of the medium become when the wave passes through.
In a longitudinal wave, what term is a measure of how compressed particles of the medium become when the wave passes through?