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

[EX Q]: The behavior of ideal gases is explained by kinetic molecular theory.
[EX A]: The behavior of ideal gases is explained by what theory of gases?

[EX Q]: Most ferns produce the same type of spores and are therefore called homosporous.
[EX A]: Most ferns produce the same type of spores and are therefore called what?

[EX Q]: Direction describing motion, what factor is just as important as distance.
[EX A]:
When describing motion, what factor is just as important as distance?