Answer:
(a) 1, 2 and 4
Explanation:
Countries frequently mentioned in the media for their low birth rates, ageing population, or declining population include:
Italy: Known for its low birth rates and ageing population.
Japan: Frequently cited for its ageing population and very low birth rates.
South Korea: Also mentioned for its low birth rates and concerns about a declining population in the future.
Nigeria and South Africa are not typically mentioned in the context of low birth rates or ageing population. Nigeria, in particular, has a high birth rate and a young population.
Therefore, the correct answer is (a) 1, 2 and 4.