A national population pyramid shows a narrow base, tapering sides and a relatively broad upper portion representing the elderly. The most likely interpretation is:
- A A rapidly growing population with high fertility
- B A stationary population with equal proportions in all age groups
- C A declining population with low birth rates and an ageing age structure ✓
- D Data error due to under-enumeration of children
Correct answer: C. A declining population with low birth rates and an ageing age structure
Explanation
A pyramid with a narrow base indicates few births, reflecting sustained low fertility. The broad upper portion reflects a large elderly cohort surviving due to low mortality, giving a constrictive or urn-shaped profile typical of countries such as Japan. Expansive pyramids have wide bases (option A), and truly stationary populations show near-parallel sides up to older ages before tapering (option B). A consistent narrow base across surveys represents genuine low fertility, not enumeration error.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.