TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Combustion reaction occurs when a substance reacts quickly with oxygen.

SOLUTION: What occurs when a substance reacts quickly with oxygen?

PROBLEM: The metallic bond is responsible for the properties of metals.

SOLUTION: What is responsible for the properties of metals?

PROBLEM: Sporopollenin protects the pollen of seed plants and spores of seedless plants.

SOLUTION:
What protects the pollen of seed plants and spores of seedless plants?