Consider the following pairs:
1. Economic Growth: Increase in economic variables over a period of time.
2. Economic Development: Improvement in the standard of living from low-income to high-income.
3. Progress: Specific economic connotations focused on quantifiable metrics.
4. World Happiness Report: Resource provided by the World Bank.
How many pairs given above are correctly matched?
Correct answer is option 'B'. Can you explain this answer?