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

Ex Input:
Solid is characterized by molecules with minimal movement and strong forces between them.

Ex Output:
Which state of matter is characterized by molecules with minimal movement and strong forces between them?


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

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


Ex Input:
One function of the cardiovascular system is to transport gases throughout the body.

Ex Output:
Which is a function of the cardiovascular system?