According to Malthus famines and drought are important to control population growth. They are called:

Positive checks

The correct answer is Option (3) → Positive checks

According to Malthus, famines and drought are considered "Positive checks" on population growth. These checks are factors that increase mortality rates, thereby reducing population growth by decreasing the number of people in a population. Malthus argued that positive checks such as famine, disease, and war were necessary to keep population growth in check and prevent population size from exceeding available resources.