Q. For India, China, the UK and the USA, which one of the following is the correct sequence of the median age of their populations? (UPSC Prelims 2008)
Answer: India < China < UK < USA
Notes: The median age of a population reflects the age at which half the population is younger and half is older. India has the youngest median age among these four nations due to its high fertility rate and young population structure. China's median age is higher than India's because of its one-child policy (1979-2015), which reduced birth rates significantly. The UK and USA have older median ages as developed nations with lower fertility rates and aging populations. The UK typically has a slightly higher median age than the USA due to demographic patterns in European countries. Therefore, the correct sequence from youngest to oldest median age is: India < China < UK < USA.