Question

give one reason for the state which are highly populated and low populated

Answer 1

pollution and their parties

Answer 2

the reason for the vast difference in population in states is the geographical and social,cultural and economic factors. The natural growth rate is also one cause
if you want more description you can add these lines:
-topography:people prefer to live in plains rather than mountains and plateaus because these areas are suitable for farming
-climate:people usually avoid extreme climates that are very hot or cold.
-soil:fertile soils provide suitable land for agriculture
-water:people prefer to live in the areas where fresh water is easily available.
-minerals:areas with availability of minerals are more populated
-social:areas with better housing,education and health facilities are more densely populated.
-cultural:places with religious and cultural significance attract people
-economic:industrial areas provide employment opportunities.