During a certain period, a country with a constant population expands its output per head. It also experiences a significant increase in river and atmospheric pollution. In the absence of any other changes, which measure would show a decrease in living standards?

1. During a certain period, a country with a constant population expands its output per head. It also experiences a significant increase in river and atmospheric pollution. In the absence of any other changes, which measure would show a decrease in living standards? A Gross Domestic Product per head B Gross National Product per head C Human Development Index D Measure of Economic Welfare[1]