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

Input: Consider Input: Demagnetization is the process in which a magnet loses its magnetic properties.

Output: What is the process called in which a magnet loses its magnetic properties?

Input: Consider Input: A frog develops (a/an) lungs as it changes from a tadpole to an adult frog.

Output: Which of the following structures does a frog develop as it changes from a tadpole to an adult frog?

Input: Consider Input: Streams often start in mountains.
Output: Where do streams often start?