TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Simple carbohydrates can be classified in terms of chain length.

SOLUTION: Which carbohydrates can be classified in terms of chain length?

PROBLEM: Over 90% of the energy we use comes originally from the sun.

SOLUTION: Over 90% of the energy we use comes originally from what?

PROBLEM: The flexibility of an object allows it to bend.

SOLUTION:
Which property of an object allows it to bend?