Which answer best indicates the dynamic balance of an ecosystem?

number of plants vs. number of animals
number and variety of organisms vs. changing environment
number of organisms vs. constant environment

For the answer to the question which answer best indicates the dynamic balance of an ecosystem?
The answer is the second one among the given choices which is
number and variety of organisms vs. changing environment.
I hope my answer helped you.

C. gemstones they are the only non metallic mineral from the list.