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

Southern asia does the most important monsoon in the world occur.
Where does the most important monsoon in the world occur?

Cancer occurs most often in adults over fifty age.
Cancer occurs most often in adults over what age?

Photoemissive are materials that eject electrons when illuminated with light called.
What are materials that eject electrons when illuminated with light called?