Question

multiple - choice question
where are nitrogen fixing bacteria found? (select all that apply)
plant roots
water
soil
air

Explanation:

Nitrogen - fixing bacteria can form symbiotic relationships with plant roots (e.g., rhizobium in legume roots). They are also present in soil where they contribute to the nitrogen cycle. Some can be found in water. They are not abundant in air as their main activity is related to soil - and plant - associated nitrogen transformation.

Answer:

plant roots, water, soil