Name the four fibre crops grown in India? Which one of them is not obtained directly from the crops? What is the name given to process involved in its production?

(a) Four fibre crops grown in India are cotton, jute, hemp and natural silk.
(b) The first three i.e., cotton, jute and hemp are derived from the crops grown in the soil. Natural silk is obtained from the cocoons of the silkworm.
(c) Rearing of silk worms for the production of silk fibre is known as sericulture.