In a population there were 20 individuals. Now birth rate is 2 and death rate is zero. What will be the existing number of individuals in the population?

The correct option is B 22
Population growth rate (PGR) is the increase in a country's population during a period of time, usually one year, expressed as a percentage of the population at the start of that period. It reflects the number of births and deaths during a period and the number of people migrating to and from a country.

As there are 20 individuals, birth rate is 2 and death rate is 0, also there is no migration. Therefore, 20+2-0=22.

Therefore, the correct answer is option B.