An ecosystem is best described by which of the following?

a) a population of fish in a small lake

b) the wood of a rotting log

c) a flock of birds in the air

d) an entire desert, including abiotic and biotic factors

The answer is D) An entire desert, including abiotic and biotic factors. An ecosystem is not an ecosystem without abiotic and biotic factors. Fish, birds, and wood are all parts of an ecosystem, but without abiotic and biotic factors, they aren't apart of anything.

~Silver