TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: A collapsing nebula leads to nuclear fusion process.

SOLUTION: A collapsing nebula leads to what process?

PROBLEM: Molar masses can be used to determine the mass of a quantity of material.

SOLUTION: What can be used to determine the mass of a quantity of material?

PROBLEM: Chemosynthesis helps microorganisms make food with chemicals pouring out of deep-sea vents.

SOLUTION:
Which process helps microorganisms make food with chemicals pouring out of deep-sea vents?