Answer:
(Part A)
Population aging is the increase in the average age of the population due to certain demographic factors such as Low fertility rates and increased life expectancy etc.
(Part B)
Population aging affects the population by making it to be composed mainly by AGED MEMBERS.
It also leads to reduced Productivity as the aged members will be less Productive as compared with the young population.
(Part C)
The demographic factors includes
LOW FERTILITY RATES
INCREASED LIFE EXPECTANCY
IMMIGRATION
EMIGRATION ETC
Explanation: Population aging is a major factor that can lead to reduced Productivity within an economy,an aged population is generally characterized by the presence of Aged members of society.
Several factors such have been attributed to population aging such as LOW FERTILITY RATES,INCREASED LIFE EXPECTANCY,IMMIGRATION INTO THE COUNTRY OF AGED POPULATION AND EMMIGRATION OUT OF THE COUNTRY BY THE YOUNG POPULATION.