Explanation:

 Peaty and marshy soils are found in Kerala, coastal track of Orissa, Sunderban area of W.B. So, (a) is wrong.
 A soil that is diffused with Iron generally develops red colour, and in hydrated form occurs in yellow colour. This criteria is fulfilled by red and yellow soil. So, (b) is correct
Laterite soil occurs in region of high rainfall. So, (d) can be ruled out.
Black soils also develop over crystalline igneous rocks but they are concentrated in the western half of Peninsula and are absent from the eastern part.