Which of the following options incldes biofertilscrs ?
A. cowdung manure and farmyard waste
B. A quick growing crop ploughed back into the field
C. Nostoc, Oscillatoria
D. All of these
Answer:C
Which of the following options incldes biofertilscrs ?
A. cowdung manure and farmyard waste B. A quick growing crop ploughed back into the field C. Nostoc, Oscillatoria D. All of these