Answer:
Nitrogen fixation is the conversion of gaseous nitrogen into an organism friendly form (ammonia) .
Explanation:
Nitrogen fixation -
It is very important and necessary process by which the nitrogen gas present in the atmosphere gets converted to nitrogen derivatives like ammonia in the soil , is referred to as the process of nitrogen fixation.
This occurs due to the reason , that the derivatives of nitrogen are of much more importance than the molecular nitrogen.
Biologically the process is done by the rhizobium bacteria .
Hence ,
From the question,
The correct option is a.
