The number of organisms in a population is added by:

The crude number of births by a population per unit time is called:

The tiger census in our national parks and tiger reserves is based on:

At one time,the number of cheetahs in a habitat is $80$. Their birth rate is $4$ and death rate is $2$. Among them,$6$ cheetahs are internal migrants (immigration) and $3$ cheetahs are migratory (emigration). Calculate the population density of cheetahs in that habitat.

The percentage of the population of India living in Madhya Pradesh $(M.P.)$ at present is approximately: (in $\%$)

Under a particular set of selection pressure,organisms evolve towards the most efficient reproductive strategy. For example:
$A$) Oysters produce a large number of small-sized offspring.
$B$) Mammals produce a small number of large-sized offspring.
In the light of the above statements,choose the correct option.