Green manure is
sesbania
Green Manure:
Crops that are grown to increase the fertility of the soil are called green manure.
The correct option is D:
The explanation of the correct option.
Sesbania is a leguminous plant that increases the fertility of the soil by fixing nitrogen in the soil.
The explanation of the incorrect option.
Option (a)-
Rice is not green manure.
Option (b)-
Sorghum is not used as green manure.
Option (c)-
Maize is not used as green manure.
Final Answer: Sesbania is green manure.