Answer : 1. "राष्ट्रीय आय/देश की कुल जनसंख्या"
Explanation :

The average income of the people of a country in a particular year is called Per Capita Income for that year. So, it is National Income divided by population.

Per Capita Income

= National Income/Total population of the country

Though Per Capita Income is more reliable than GNP for many particular purpose.