For populations that are said to be in a zero growth phase, which of the following is MOST LIKELY occurring?

A country that is in a zero population growth phase has stable numbers related to the number of individuals in the population. This can be achieved if the birth rate is equal to the death rate and if the emigration rate is equal to immigration rate. In essence, for each individual that leaves the population either through death or emigration, the individual is replaced by the immigration or birth of another.