A Free-living Non-photosynthetic aerobic nitrogen-fixing Bacterium is
A. Azotobacter
B. Nostoc
C. Rhizobium
D. Azospirillium
Answer:A
A Free-living Non-photosynthetic aerobic nitrogen-fixing Bacterium is
A. Azotobacter B. Nostoc C. Rhizobium D. Azospirillium