Concept: Rapid population growth increases the number of people, especially young dependents, who rely on others for support.Explanation:• Rapid population growth leads to many children and young people who are not yet working.• This creates a high dependency burden, because fewer workers must support many dependents.• The other options are not typical effects: production usually needs to increase, standards of living usually fall, and productivity may be affected but dependency burden is the clearest social effect.Answer: B. High dependency burden