Salts are drawn to the surface of the soil by:

The correct answer is Option (3) → Water logging

Option (1) Over cultivation — Incorrect. Over-cultivation removes the fertile top-soil and leads to soil erosion and desertification, not to salt at the surface.

Option (2) Deforestation — Incorrect. Cutting forests leaves the soil bare, so it is washed or blown away (soil erosion).

Option (3) Water logging — Correct. Of the four, only waterlogging is linked by NCERT to salt: when irrigation water is not drained, it brings salt up to the soil surface. The other three cause soil erosion and desertification instead.

Option (4) Unrestricted grazing — Incorrect. Unrestricted grazing removes the plant cover and causes soil erosion and, over time, desertification.

Note: This question is from Chapter 16, Environmental Issues, of the pre-rationalised NCERT book. This chapter is not in the present NCERT book (2026-27). The extract below is from the pre-rationalised edition.

NCERT Extract (Pre-rationalised edition, Chapter 16, Environmental Issues):
Degradation by Improper Resource Utilisation and Maintenance – “… Waterlogging and soil salinity: Irrigation without proper drainage of water leads to waterlogging in the soil. Besides affecting the crops, waterlogging draws salt to the surface of the soil. The salt then is deposited as a thin crust on the land surface or starts collecting at the roots of the plants.”