Step 1: Concept Identification: The objective is to select a factually correct statement regarding demography, the statistical analysis of human populations.
Step 2: Detailed Analysis:
(A) Demographic change is purely biological: Incorrect. While births and deaths are biological events, their rates (fertility and mortality) are significantly influenced by social, economic, and cultural factors such as education, healthcare, religion, and economic development.
(B) Demographic data is a static data for a population: Incorrect. Demographic data is inherently dynamic, with populations continuously changing due to births, deaths, and migration.
(C) Population explosion does not happen in every country: True. The 'population explosion' is characteristic of Stage 2 of the demographic transition. Some nations, like France, experienced a slower transition without the dramatic population booms observed elsewhere. However, option (D) presents a more fundamental and overarching statement.
(D) Demographic change is based on economic, social and cultural variables: This is the most accurate and fundamental statement, representing the core principle of modern demography and the demographic transition theory. Key drivers of changes in birth and death rates include women's education, urbanization, healthcare access, and economic conditions. This statement explains the underlying causes of demographic patterns, including population explosions.
Step 3: Conclusion: The most comprehensive and accurate statement is that demographic change is a result of the complex interaction of economic, social, and cultural variables.