Explanation

• 1. Italy (Correct): Regularly highlighted for its demographic crisis in Europe, having one of the world’s lowest fertility rates (~1.2 births per woman) and one of the highest median ages (~48 years), leading to a steadily shrinking and ageing population.

• 2. Japan (Correct): The classic global case of a “super-aged” society where people aged 65 and older make up nearly 30% of the population, facing sustained natural population decline for over a decade.

• 3. Nigeria (Incorrect): Represents the opposite demographic trend; it has a very high total fertility rate (>4.5) and a booming, youthful population (median age under 19 years).

• 4. South Korea (Correct): Consistently reported for having the lowest total fertility rate in the world (plummeting below 0.75), facing rapid demographic aging and an acute population cliff.

• 5. South Africa (Incorrect): Has a relatively young population profile with a fertility rate well above replacement level (~2.3), making it non-applicable to aging/depopulation media coverage.

Hence, the correct answer is 1, 2, and 4 only.

Key Facts (Demographic Terminology & Trends):

• Replacement-Level Fertility: Roughly 2.1 births per woman, the total fertility rate (TFR) required for a population to exactly replace itself from one generation to the next without migration.
• Super-Aged Society (UN Definition): A country where 20% or more of the total population is aged 65 or older (e.g., Japan, Italy, Germany).
• Demographic Trap / Window: Rapid population aging leads to a rising dependency ratio, shrinking labor workforce, higher pension/healthcare burdens, and lower economic growth potential.