Demography

Age structure of population refers to the classification and distribution of people into different age groups within a country or region at a particular point of time. It shows how many people belong to the young, adult, and old age categories. In other words, it helps us understand the composition of a population based on age.
The age structure is generally divided into three broad groups:

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  Pre-reproductive Age Group (0–14 years): This group includes children who are not yet capable of reproduction. They are economically dependent on the working population for their basic needs such as food, education, and healthcare. A large proportion in this category usually indicates future population growth.
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  Reproductive or Working Age Group (15–59 years): This group consists of adults who are capable of working and earning. They contribute to the economic development of the country and support both the young and the elderly population. A higher percentage in this group is considered beneficial for economic growth.
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  Post-reproductive Age Group (60 years and above): This group includes elderly people who are generally not economically active. They depend on the working population for support. A higher proportion in this group indicates an ageing population.

The age structure is important because it helps in planning for schools, employment opportunities, healthcare facilities, pensions, and other social services. It also indicates whether a population is growing, stable, or declining. For example, a population with a broad base in its age pyramid (more children) shows rapid growth, while a narrow base indicates slow or negative growth.
Therefore, age structure is a key demographic indicator that helps governments and policymakers in making economic and social development plans.

Population growth rate is the rate at which the number of individuals in a population increases or decreases over a specific period of time, usually one year. It indicates how fast a population is expanding or shrinking.
The growth of a population depends mainly on four important factors: birth rate, death rate, immigration, and emigration. Birth rate increases the population as new individuals are added. Death rate decreases the population as individuals die. Immigration adds people to the population from outside areas, while emigration reduces the population when people move out.
If the number of births and immigrants is greater than the number of deaths and emigrants, the population shows a positive growth rate. If deaths and emigration are higher, the growth rate becomes negative. When births and deaths are equal and migration is balanced, the population remains stable.
Population growth rate is generally expressed as a percentage. It can be calculated using the formula:
Population Growth Rate = (Births + Immigration − Deaths − Emigration) ÷ Total Population × 100
Thus, population growth rate helps in understanding population trends and planning for resources such as food, housing, education, and healthcare.

Step 1: Understanding the term ‘Demography’.
The word "Demography" is derived from two Greek words — “Demos” meaning people and “Graphy” meaning description or study. Therefore, demography literally means the study of population.

Step 2: Analysis of the options.

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  (A) Latin: Incorrect. The term does not originate from Latin.
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  (B) Greek: Correct. Both parts of the word are derived from Greek language.
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  (C) English: Incorrect. English adopted the word but it is not the origin.
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  (D) French: Incorrect. The origin is not French.

Step 3: Conclusion.
Since the word is derived from Greek words, the correct answer is (B) Greek.

Final Answer:} Greek.