Concept:Malthus's positive checks are natural forces that raise the death rate when population growth outstrips food supply.
Explanation:Thomas Malthus identified two types of population checks: positive checks and preventive checks.
Positive checks include famine, war, disease, pestilence, floods, and other natural calamities.
These disasters cause the death rate to rise sharply, restoring the balance between population and food supply.
Such harsh checks occur mainly when the population presses hard on available food resources.
Therefore, positive checks can be prevented if the death rate is reduced through improved healthcare, adequate food, and better living conditions.
Abolishing moral restraint would remove voluntary birth control, making positive checks more likely, not less.
Natural calamities themselves are positive checks, so they cannot prevent positive checks.
Thus, controlling the death rate is the most effective way to avoid Malthus's positive checks.
Answer:A. death rate is reduced.