GNP per head in a country has risen by 10% during the last 5 years. What is not a valid reason for questioning whether average living standards have also increased by the same amount?
- AThe distribution of income may have changed considerably over the period.
- BThe general price level is likely to have changed over the period.
- CThe size of the population may have changed over the period.
- DThe workforce may have produced greater output by working for more hours per week.