Natality refers to:

In ecology and population studies, Natality is essentially the scientific term for the birth rate. It represents the production of new individuals in a population through reproduction (birth, hatching, or germination).Breakdown of the OptionsTo help you keep these straight for future reference, here is what each term actually describes:A) Natality: The number of births added to the initial population density over a specific time.B) Mortality: The number of deaths in a population during a given period.C) Immigration: The influx of individuals into a habitat from elsewhere.D) Emigration: The movement of individuals out of a population/habitat.Why it mattersThese four factors work together to determine whether a population grows or shrinks. The basic formula for population change is:$$Density_{(t+1)} = Density_t + [(Natality + Immigration) - (Mortality + Emigration)]$$