Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: Elastic rebound theory. Stresses build on both sides of a fault. The rocks deform plastically as seen in Time 2. When the stresses become too great, the rocks return to their original shape. To do this, the rocks move, as seen in Time 3. This movement releases energy, creating an earthquake. Answer: elastic rebound theory
A:
What theory says stresses build on both sides of a fault?