Question

From 1951 to 1981 the annual rate of population increased why

Answer 1

bescause the

health facilities improved

the education facilities

better sanitation

Answer 2

From 1951 to 1981 the annual rate of the population increased because of the decreasing death rate (more quickly than the birth rate) and mostly the human age averagely increasing.  

Death and Births, these two are natural causes for the populations. The difference like Population growth = birth rates – death rates and it’s called natural increased.