Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Air quality is a measure of pollutants in the air.

Output: Air quality is a measure of what in the air?


Input: Consider Input: 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.

Output: 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?


Input: Consider Input: Human overpopulation is crowding out other species and making all the other causes of extinction worse.
Output: What phenomenon is crowding out other species and making all the other causes of extinction worse?