Which of the following is NOT a reason for the increase in urban population?

Net out-migration.

The correct answer is option 3: Net out-migration.

Option 1: Natural increase — Reason for increase. Urban population increases when births exceed deaths.

Option 2: Net in-migration — Reason for increase. Movement of people from rural areas or other regions into urban areas increases urban population.

Option 3: Net out-migration — Not a reason for increase. Net out-migration means more people are leaving urban areas than entering them, which decreases urban population rather than increasing it.

Option 4: Reclassification of urban areas to encompass formerly rural population settlement — Reason for increase. When rural settlements are reclassified as urban areas, the urban population increases statistically.

NCERT: Urban population grows as a result of natural increase (when birth rate exceeds death rate), net in-migration (when people move in than out), and sometimes reclassification of urban areas to encompass formerly rural population settlements. In India, it is estimated that after 1961 around 60 per cent of the urban growth has been attributed and 29 per cent of them from rural areas to urban migration.