TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Line graphs are especially useful for showing changes over time.

SOLUTION: Line graphs are especially useful for showing changes over what?

PROBLEM: Starches are complex carbohydrates that are the polymers of glucose.

SOLUTION: What complex carbohydrates are the polymers of glucose?

PROBLEM: It is an inherited behavior that maintains the population statement explains why most salmon leave salt water and return to fresh water.

SOLUTION:
Which statement explains why most salmon leave salt water and return to fresh water?