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?"

Q: Fact: muscular walls of blood vessels contracting raises blood pressure.

A: what happens when muscular walls of blood vessels contract?
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Q: Fact: deepening rivers cause the loss of topsoil.

A: Deepening rivers cause?
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Q: Fact: CO 2 concentrations in the air have increased over the last decade dramatically.

A:
What has increased in the air dramatically over the last decade?
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