Answer :
The correct answer is (c) Cause a decrease in growth rate.
Emigration is a term which is used to define movement of individual(s) permanently out of population. Reason of emigration can be search of new areas for food, shelter and overcrowding. The rapid increase in the emigration of a country will result in decrease in the growth rate. The growth rate is defined as the increase in population over a period of time. The population is decreasing due to the emigration the growth rate will also decrease.