Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
--------
Question: You call the separation of ions that occurs when a solid ionic compound dissolves dissociation.

Answer: What do you call the separation of ions that occurs when a solid ionic compound dissolves?

Question: Fermat's principle states that light will always take the path of the least amount of time.

Answer: Fermat's principle states that light will always take the path of least amount of?

Question: At the poles are temperatures the lowest.

Answer:
Where are temperatures the lowest?