All of the Following are Free-Living Nitrogen-Fixing Bacteria Except

Question

All of the following are free-living nitrogen-fixing bacteria except
A)Clostridium.
B)Bacillus.
C)Rhizobium.
D)Azotobacter.

Accepted Answer

Clostridium, Bacillus, and Azotobacter are all examples of free-living nitrogen-fixing bacteria, meaning they can fix atmospheric nitrogen into a usable form without living in a symbiotic relationship with another organism. Rhizobium, on the other hand, is a nitrogen-fixing bacteria that lives in a symbiotic relationship with plants, specifically legumes. Therefore, the correct choice is C, Rhizobium.