Correct Answer - C
Compost is a prepared mixture made of rotted vegetable matter and manure. An enriched composited manure is made by dumping all kinds of plant matter including garbage of vegetable markets and other organic refuse in heaps Interspersed by the thin sprinkling of chemical fertilizers like ammonium sulphate, superphosphate, sodium nitrate, lime etc. It requires-6 months for preparation of manure. Green manure is prepared from young, green crop plants by ploughing them back into soil. Usually young leguminous crops are used for green manuring because they also increase the nitrogen fertility of the soil. The plants are slowly converted into manure through the activity of micro organisms.
