Sneezing is an involuntary action because it's something we cannot control.
<span>The answer should be: D) water supply
</span>Water is a perishable resource and its supply will limit how much population that an area could hold. <span>With a bigger population, the competition for water will be higher which make water shortage more likely. Others density-dependent limiting factor than competition would be disease, parasitism, and predation.
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