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

[EX Q]: Urea is made in the liver and excreted in urine.
[EX A]: What is made in the liver and excreted in urine?

[EX Q]: Fermat’s principle states that light will always take the path of the least amount of time.
[EX A]: Fermat’s principle states that light will always take the path of least amount of?

[EX Q]: The the core is the innermost layer of the sun.
[EX A]:
What is the innermost layer of the sun called?