What is the best description of the relationship between GDP per capita and life expectancy, and what does that imply about causation?

• A. GDP per capita directly causes life expectancy; proven causal.
• B. Higher income often relates to better health and longer life, but correlation does not prove causation.
• C. There is no relationship; it's random.
• D. Life expectancy causes GDP per capita to rise.

Answer: (B)

The main idea is that GDP per capita and life expectancy tend to move together: richer countries generally enjoy longer average lifespans because more resources can fund better nutrition, healthcare, sanitation, education, and overall living conditions. But this observed relationship is a correlation across many countries and over time, not a proven cause-and-effect link. There are many pathways involved: higher income can enable health improvements, but good health can also help a economy grow by boosting productivity; both can be driven by other factors such as trustworthy institutions, stable governance, or public health policies. Because of these intertwined factors and time lags, simply having more income doesn’t automatically prove it causes longer life.