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

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


[Q]: The love canal tragedy was an infamous example of industrial waste dumping.
[A]: Love canal was an infamous example of what type of pollution?


[Q]: Diffusion is the process in which a substance naturally moves from an area of higher to lower concentration.
[A]:
What is the process in which a substance naturally moves from an area of higher to lower concentration called?