The black cotton soil of India has been formed due to the weathering of

The black cotton soil of India has been formed due to the weathering of
  1. brown forest soil
  2. fissure volcanic rock
  3. granite and schist
  4. shale and limestone

Solution

Black cotton soil (regur) is formed from the weathering of basaltic (fissure volcanic) rocks of the Deccan Trap. It is rich in iron, lime and calcium, and is moisture-retentive.

Asked in: UPSC Prelims 2021

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