Birth rate is directly proportional to

$Statement 1$: Over-population has become a serious problem in the developing countries.
$Statement 2$: It does not exhaust natural resources, causes unemployment and pollution.

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

At present,the total population of the world is about:

Statement $1$: Human population doubles after every $35 \; \text{years}$ as against $200 \; \text{years}$ in $1600-1800$.
Statement $2$: Rapid increase is due to better health facilities.

$A$: Every sixth person in the world is an Indian.
$R$: Life expectancy depends upon average life span.