Demographic Transition Model

Steps:

• Identify stages of economic development: Developing countries start with high birth and death rates, then transition to lower rates with industrialization and education.
• Examine population indicators: As development occurs, healthcare improves, reducing mortality; education and urbanization then lower fertility.
• Evaluate choices against trends: Compare each option to standard outcomes like declining fertility and shifting employment.
• Select the consistent pattern: Fertility decline is a hallmark of moving from high to low growth phases.

Why B is correct:

• In the demographic transition model, fertility rates decline as countries develop due to increased access to education, contraception, and women's workforce participation, slowing population growth.

Why the others are wrong:

• A: Average age rises as life expectancy increases and birth rates fall.
• C: Infant mortality rate decreases with better healthcare and sanitation.
• D: Primary sector (agriculture) contracts as the economy shifts to manufacturing and services.

Final answer: B