Answer: A
Correct answer: Alluvial soil
Alluvial soil covers about 40 per cent of India’s land area, the largest share of any soil type. It occupies the whole Indo-Gangetic and Brahmaputra plain and the coastal deltas, deposited by rivers over millennia. It is also the most fertile, rich in potash, phosphoric acid and lime though poor in nitrogen and organic matter, easily worked, and renewed by each flood. It supports the most intensive agriculture in the country - wheat, rice, sugarcane and pulses. It is divided into khadar, the newer alluvium of the active floodplain, which is finer and more fertile, and bhangar, older terraces above flood level containing calcareous nodules called kankar. Black soil is second, covering the Deccan lava country and suited to cotton. Red soil covers much of the crystalline south and east, and laterite forms under heavy tropical rain that leaches out the silica.