The most widespread soil type in India is —
Explanation
Why the other options are wrong: (A) Laterite soil does not match the specific location, feature, measurement or relationship asked in the question; (B) Red soil does not match the specific location, feature, measurement or relationship asked in the question; (C) Black soil does not match the specific location, feature, measurement or relationship asked in the question. Correct (D): Alluvial soil covers about 40% of India's area