How Does Productivity Explain the Differences in Standard of Living

Multiple Choice

How does productivity explain the differences in standard of living across countries?

A) Productivity tends to be lower in countries with high population, and therefore in those countries standards of living are lower.
B) Productivity explains very little of the differences across countries in the standard of living.
C) Productivity explains some, but not most, of the differences across countries in the standard of living.
D) Productivity explains most of the differences across countries in the standard of living.