The Demographic Structure

Step 1: Understanding the theory.
The theory of population growth was introduced by Thomas Robert Malthus in his famous essay "An Essay on the Principle of Population" (1798).

Step 2: Core idea.
Malthus argued that population tends to grow geometrically (2, 4, 8, 16...) while food supply increases arithmetically (1, 2, 3, 4...). This imbalance would lead to overpopulation, scarcity, and crises.

Step 3: Conclusion.
Hence, the correct answer is Malthus.

Final Answer:

Step 1: Define birth rate and death rate.
\begin{itemize} \item Birth rate: Number of live births per 1000 people in a year. \item Death rate: Number of deaths per 1000 people in a year. \end{itemize}

Step 2: Factors responsible for birth rate in India.
\begin{itemize} \item Socio-cultural factors: Preference for large families, son preference, early marriage. \item Economic factors: Poor families see children as assets for labor and income. \item Illiteracy: Lack of awareness about family planning. \item Religious beliefs: Some communities discourage contraceptives. \end{itemize}

Step 3: Factors responsible for death rate in India.
\begin{itemize} \item Healthcare facilities: Limited access in rural areas raises mortality. \item Malnutrition and poverty: Poor nutrition weakens immunity, increasing deaths. \item Epidemics and diseases: Lack of sanitation causes diseases like cholera, malaria, etc. \item Improvement in medical facilities: Decline in death rate in recent decades due to hospitals, vaccination, and awareness. \end{itemize}

Step 4: Conclusion.
India’s high birth rate and declining death rate together contribute to population growth. Final Answer (Option 1):

Step 1: Background.
Thomas Robert Malthus presented his theory in the book "An Essay on the Principle of Population" (1798).

Step 2: Core idea.
Population increases in a geometric ratio (2, 4, 8, 16...), while food supply increases in an arithmetic ratio (1, 2, 3, 4...).

Step 3: Consequence.
This imbalance leads to overpopulation, scarcity of resources, and natural checks like famine, disease, and war.

Step 4: Criticism.
Modern agriculture and technology have disproved the inevitability of crises, but the theory remains important for highlighting population-resource balance.

Final Answer: