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: Bacteria can cause bodily tissues to swell.
Bacteria can cause what?

Fact: Ozone depletion results in higher levels of DNA damage and mutations.
Ozone depletion causes higher levels of which of the following?

Fact: Cells are so small, they are the building blocks of organisms.

Cells are what, so they are the building blocks of organisms?