The most important factor which determined the increase in human population in India during the 20th century :

Options

A. Natality
B. Mortality
C. Immigration
D. Emigration

Answer

**Step-by-Step Text Solution:**

1. **Understanding Population Dynamics**: The population of a region is influenced by several factors, including natality (birth rate), mortality (death rate), immigration (inward movement of individuals), and emigration (outward movement of individuals).

2. **Defining Natality**: Natality refers to the birth rate in a given area, typically measured as the number of births per 1000 individuals in that area. A high natality rate contributes to population growth.

3. **Defining Mortality**: Mortality is the death rate in a population, also measured per 1000 individuals. A decrease in mortality rates usually leads to an increase in population since fewer individuals are dying.

4. **Understanding Immigration and Emigration**: Immigration is the movement of individuals into a population, which can increase population size. Conversely, emigration is the movement of individuals out of a population, which can decrease population size.

5. **Analyzing the Factors in India**: In India during the 20th century, the natality rate was high, meaning that there were many births. At the same time, the mortality rate was decreasing, which means fewer people were dying. Immigration was also contributing to population growth, but the primary factor was the high birth rate.

6. **Conclusion**: The most significant factor that determined the increase in the human population in India during the 20th century was the increase in natality (birth rate).

**Final Answer**: The most important factor which determined the increase in human population in India during the 20th century is **natality** (birth rate).

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