Turn the given fact into a question by a simple rearrangement of words. This typically involves replacing some part of the given fact with a WH word. For example, replacing the subject of the provided fact with the word "what" can form a valid question. Don't be creative! You just need to rearrange the words to turn the fact into a question - easy! Don't just randomly remove a word from the given fact to form a question. Remember that your question must evaluate scientific understanding. Pick a word or a phrase in the given fact to be the correct answer, then make the rest of the question. You can also form a question without any WH words. For example, "A radio converts electricity into?"
--------
Question: Fact: the moon forms tides.

Answer: what forms tides?


Question: Fact: The ovaries are used to have children.

Answer: What is used to have children?


Question: Fact: P-waves and S-waves can be traced back to faulting of rock in Earth's crust.

Answer:
The origin of P-waves and S-waves can be traced back to what?