TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Stimulation of triglyceride breakdown is the first direct action of growth hormone.

SOLUTION: What is the first direct action of growth hormone?

PROBLEM: Multiple genes mutations is usually necessary to develop cancer.

SOLUTION: What is usually necessary to develop cancer?

PROBLEM: Slowing down causes light to refract.

SOLUTION:
What causes light to refract?