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 size and symmetry of a beetle’s or an elk’s antlers or a grasshopper’s song communicate rather clearly their state of health.

Answer: The size and symmetry of a beetle’s or an elk’s antlers or a grasshopper’s song communicate rather clearly their state of what?


Question: Elements are pure substances that make up all matter.

Answer: Elements are pure substances that make up what?


Question: Growth stops when a population reaches the carrying capacity.

Answer:
What occurs when a population reaches the carrying capacity?