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

Example Input: Collision frequency is greater for homogeneous category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'.
Example Output: Collision frequency is greater for what category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'?

Example Input: Socket secures teeth in the mouth.
Example Output: What secures teeth in the mouth?

Example Input: Lipids are broken down by lipases.
Example Output:
Lipids are broken down by what?