Which of the following are the reasons for population explosion?
(i) Increased health facilities
(ii) Rapid increase in MMR
(iii) Rapid increase in IMR
(iv) Rapid decrease in MMR
(v) Decrease in number of people reaching reproductive age

The correct option is A (i) and (iv)
Rapid increase in population over a relatively short period of time is called population explosion. Reasons for population explosion are increased health facilities, decrease in MMR (maternal mortality rate), and IMR (infant mortality rate) and increase in number of people reaching reproductive age.