What are the probable factors that contributed to the population explosion in India?

(A) The probable factors contributing to the population explosion in India are as follows:
$(i)$ Decline in death rate,particularly the maternal mortality rate $(MMR)$ and infant mortality rate $(IMR)$.
$(ii)$ Better public health facilities and improved medical care leading to increased longevity.
$(iii)$ An increase in the number of people in the reproductive age group.
$(iv)$ Lack of awareness and education regarding reproductive health and family planning methods.
$(v)$ Social factors such as the preference for a male child and the belief that more children contribute to more labor and income for the family.