Question

The present century has witnessed a remarkable increase in the population of India. One major factor for this is that
A. Older people have begun to live longer
B. More children are born in each family
C. More children per family have begun to reach the reproductive age
D. More people are marrying in the younger age group

Answer 1

Hint: A population can be defined as a group of organisms of one species occupying a defined geographical area share or compete for similar resources and potentially interbreed and usually isolated to some degree from other similar groups.

Complete answer: The size of a population for any species is not a static parameter but it is ever-changing depending upon various factors including food availability, predation pressure, and adverse weather. This fluctuation in population size gives some idea of what is happening to the population whether it is flourishing or declining. The density of a population in a given habitat during a given period fluctuates due to changes in four basic processes- two of which (natality and immigration) contribute to an increase in population density and two (mortality and emigration) to a decrease.
Now let us collect information about the given options:
-Older people have begun to live longer: This is the most important factor in population growth as older people are living day by day more than these contribute to the population growth as life expectancy is increasing. It means that the death rate is decreasing.
-More children are born in each family: When more children are born in a family, it may lead to population growth but not at a time because. The children take time to contribute to future resources. But these children can lead to death and the death rate may increase
-More children per family have begun to reach the reproductive age: When more children reach the reproductive aid age, it also leads to more population growth, But it takes time to reach a sudden growth. More reproduction does not mean less death rate.
-More people are marrying in a younger age group: When more people marry in a younger age group, it leads to more reproductive age. People which contribute to the population growth but not on the sport at a time.
So, the correct answer is option A, i.e., Older people have begun to live longer.

Note: Population growth increase is due to two factors. The first one is natality and the second one is immigration. Natality is defined as the birth rate during a given. And immigration is defined as the number of individuals that come into a particular area and increase population. And population growth decreases due to two factors, that is mortality and emigration. Mortality is defined as the death rate during a given period of time.