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?"

Fact: Birds can carry seeds in their feathers.
What is carried in birds feathers?

Fact: if food is not immediately used for energy then that food will be converted into fat.
if food is not immediately used for energy then that food will be converted into what?

Fact: chemical changes can be used to kill existing microorganisms in the food.

what can be used to kill existing microorganisms in food?