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

Ex Input:
Opaque is the term for matter that does not let any light pass through.

Ex Output:
What is the term for matter that does not let any light pass through?

Ex Input:
Oxygen gas is given off by plants.

Ex Output:
Which gas is given off by plants?

Ex Input:
Explosive waste type of waste is likely to explode.

Ex Output:
What type of waste is likely to explode?