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

[EX Q]: Macroevolution happens when forces of evolution work over a long period of time.
[EX A]: What happens when forces of evolution work over a long period of time?

[EX Q]: Bile acids, needed to emulsify lipids, are stored in the body in the gallbladder.
[EX A]: Where are bile acids, needed to emulsify lipids, stored in the body?

[EX Q]: The sun delivers power to the chemical factory chloroplasts.
[EX A]:
What delivers power to the chemical factory chloroplasts?