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

[EX Q]: Diffraction is the phenomenon in which light and sound waves become circular at the point source of a barrier.
[EX A]: What is the phenomenon in which light and sound waves become circular at the point source of a barrier?

[EX Q]: All cells have the small size in common.
[EX A]: What do all cells have in common?

[EX Q]: Aerobic exercise helps improve the cardiovascular system, while anaerobic exercise causes muscles to get bigger and stronger.
[EX A]:
Aerobic exercise helps improve the cardiovascular system, while what exercise causes muscles to get bigger and stronger?