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

[EX Q]: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the capillaries.
[EX A]: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the what?

[EX Q]: Poles parts of the planet does solar energy have difficulty reaching.
[EX A]: What parts of the planet does solar energy have difficulty reaching?

[EX Q]: By exploding bolts the space probes get separated from their launchers.
[EX A]:
By exploding what the space probes get separated from their launchers?