Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Intraplate earthquakes occur because solid lithosphere travels on a round planet.

Output: What occur because solid lithosphere travels on a round planet?


Input: Consider Input: Embryos usually don't survive if they have extra or too few of these genetic units?

Output: Embryos usually don't survive if they have extra or too few of these genetic units?


Input: Consider Input: Gastrin signals the secretion of gastric acid.


Output: What signals the secretion of gastric acid?