The density of a population in a given habitat during a given period,…

The correct answer is Option (4) → (A), (B), (C) and (D)

(A) Natality Correct. Natality is the number of births in the population during a given period. The new individuals are added to the density.

(B) Immigration Correct. Immigration is the number of individuals of the same species that come into the habitat from elsewhere. They too raise the density.

(C) Emigration Correct. Emigration is the number of individuals that leave the habitat and go elsewhere. It lowers the density.

(D) Mortality Correct. Mortality is the number of deaths in the population during a given period. It also lowers the density.

Note: The same question was also asked in CUET (UG) 2025 on 20-05-2025 (Slot 2), and a similar question in CUET (UG) 2026 on 30-05-2026 (Slot 2) and on 22-05-2026 (Slot 1).

NCERT Extract:
Population Growth – “The size of a population for any species is not a static parameter. It keeps changing with time, depending on various factors including food availability, predation pressure and adverse weather. In fact, it is these changes in population density that give us some idea of what is happening to the population – whether it is flourishing or declining. Whatever might be the ultimate reasons, 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.”