Which country has the highest rate of natural increase?

Niger has the highest rate of natural increase among the choices provided due to its significantly high fertility rate combined with a relatively low mortality rate. Natural increase is calculated based on the difference between the number of live births and deaths in a population over a specified period. In Niger, cultural factors, such as a preference for large families and lower access to family planning resources, contribute to a high number of births each year. The country's cohort of young people, with a large portion of the population being in reproductive age, also drives this natural increase.

While Bangladesh and India have notable population growth, their fertility rates have been decreasing due to urbanization, increased access to education and healthcare, and family planning initiatives. The United States, on the other hand, has a relatively lower natural increase rate compared to Niger, mainly due to lower fertility rates coupled with a more balanced age structure. Hence, Niger stands out as the country with the highest rate of natural increase.