Given a scientific question, generate a correct answer to it.

[EX Q]: What has traditionally been defined as a force of attraction between two masses?
[EX A]: gravity

[EX Q]: What kind of planet do we consider ceres to be?
[EX A]: dwarf planet

[EX Q]: What do you call a lens that causes the light rays to bend away from its axis?
[EX A]:
diverging lens