Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: The brain is the most complex organ in the human body.

Answer: What is the most complex organ in the human body?

Question: The ileocecal valve, a sphincter, is usually in a constricted state, but when motility in the ileum increases, this sphincter relaxes, allowing food residue to enter the first portion of large intestine.

Answer: The ileocecal valve, a sphincter, is usually in a constricted state, but when motility in the ileum increases, this sphincter relaxes, allowing food residue to enter the first portion of what?

Question: Articular processes allow for the greatest range of rotation within the vertebral column and facilitate the movement of the head.

Answer:
What processes allow for the greatest range of rotation within the vertebral column and facilitate the movement of the head?