According to the passage, why is the inequality－adjusted income per head in France higher

According to the passage, why is the inequality-adjusted income per head in France higher than that in America？

A．Because the GDP per capita in France is substantially higher than in America.

B．Because France witnessed a sharp increase of inequality in income distribution.

C．Because income distribution is more polarized in America than in France.

D．Because the two countries adopted different methods of national-account measurement.

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