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?"

Example Input: Fact: Guard cells determine the water loss.
Example Output: What determines water loss?

Example Input: Fact: Astronomers study the stars and universe.
Example Output: Besides the universe, what do astronomer's study?

Example Input: Fact: Organs of excretion remove waste and toxic substances from blood.
Example Output:
What is the purpose of organs of excretion?