TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: The bird ancestor that lived in trees developed wings, which is commonly associated with birds.

SOLUTION: The bird ancestor that lived in trees developed what feature commonly associated with birds?

PROBLEM: The long, threadlike extensions of the nerve cell help transmit nerve impulses.

SOLUTION: Which part of the nerve cell helps transmit nerve impulses?

PROBLEM: Potassium hydroxide in soap is an example of base.

SOLUTION:
Potassium hydroxide in soap is an example of what?