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: cloth-edged screens are used for separating mixtures.
Example Output: what are used for separating mixtures?

Example Input: Fact: Some animals with feathers are pollinators.
Example Output: Some what with feathers are pollinators?

Example Input: Fact: Mature forms of B-lymphocytes secrete antibodies.
Example Output:
The mature form of what kind of cell secretes antibodies?