Answer:
b
Step-by-step explanation:
Giardia lambia is not known as an iron bacteria.Iron bacteria are a group of microorganisms that obtain energy by oxidizing dissolved ferrous iron in water to insoluble ferric iron, which then forms rust-colored deposits on surfaces. The other organisms listed - crenothrix, gallionella, and leptothrix - are all types of iron bacteria.
Giardia lambia, on the other hand, is a parasitic protozoan that causes a diarrheal illness called giardiasis. It does not have the ability to oxidize iron and is not classified as an iron bacteria.