The growth rate of population in India has been caused by annual birth rate, death rate and rate of migration.
B is correct answer

The low growth rate of population in India is primarily attributed to a fall in birth rate.

There are several factors that contribute to the low growth rate of population in India, but the most significant one is the fall in birth rate. Let's explore this in detail:

1. Fall in birth rate:
- One of the main reasons for the low growth rate of population in India is the significant decline in birth rate over the years. The birth rate refers to the number of live births per 1,000 individuals in a population.
- This decline in birth rate can be attributed to various factors such as increased literacy rates, awareness about family planning methods, availability of contraceptives, and government initiatives promoting family planning.
- As people become more educated and aware, they tend to plan their families better and opt for smaller family sizes. This leads to a decline in the birth rate, ultimately resulting in low population growth.

2. Fall in death rate:
- While the fall in death rate is also a contributing factor to the low population growth rate in India, it is not the primary reason.
- The death rate refers to the number of deaths per 1,000 individuals in a population. In India, the death rate has indeed decreased over the years due to improvements in healthcare, sanitation, and access to medical facilities.
- However, the decline in death rate alone is not sufficient to explain the low population growth rate, as it is outweighed by the significant decline in birth rate.

3. Fall in infant mortality rate:
- The fall in infant mortality rate, which refers to the number of deaths of infants under one year of age per 1,000 live births, is also a contributing factor to the low population growth rate in India.
- Improvements in healthcare, nutrition, and sanitation have led to a decline in infant mortality rate, ensuring that more infants survive beyond their first year.
- However, the impact of the fall in infant mortality rate on population growth is relatively smaller compared to the decline in birth rate.

4. Increase in life expectancy:
- Another factor that indirectly affects population growth is the increase in life expectancy. Life expectancy refers to the average number of years a person is expected to live.
- With advancements in medical science, healthcare facilities, and improved living conditions, life expectancy in India has increased significantly.
- However, the increase in life expectancy does not directly impact population growth as it only affects the rate at which people age, rather than the rate at which new individuals are born.

In conclusion, while factors such as a fall in death rate, fall in infant mortality rate, and increase in life expectancy contribute to the low growth rate of population in India, the primary factor is the significant decline in birth rate. The decline in birth rate can be attributed to factors such as increased education, awareness, and availability of family planning methods.