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

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: Glycerol is a triol, an alcohol which contains three hydroxl functional groups.

Output: Glycerol is a triol, an alcohol which contains three what?

Input: Consider Input: Ligaments is the term for tough protein fibers that connects bones to each other.
Output: What is the term for tough protein fibers that connects bones to each other?