Which of these is an abiotic factor of an aquarium ecosystem? a
algae growing on the glass
b
gravel on the bottom of the aquarium
c
plants growing from the gravel
d
fish swimming in the water

b

Explanation:

abiotic factors are nonliving things and gravel is nonliving so that has to be the answer

B: gravel on the bottom of the aquarium

Explanation:

Abiotic Factor means a non-living thing so gravel would be the best option.

the answer you are looking for is the united states forest service.

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