Question

if a changing environment causes a single species to become separated into two distinct groups that can no longer mix, what is the most likely long - term outcome?
speciation, because the species is adapting to a new environment.
the species would stop being part of the evolutionary process.
extinction, because its gene pool has been lost.
the species would remain exactly the same over time.

Explanation:

When a single species is separated into two non - mixing groups due to a changing environment, over time, each group will adapt to its specific environment. This can lead to genetic differences accumulating between the two groups, eventually resulting in speciation, which is the formation of new species. The other options are incorrect as the species is still part of the evolutionary process and is not likely to go extinct just because it has split into two groups, and it won't remain exactly the same over time due to environmental pressures.

Answer:

A. Speciation, because the species is adapting to a new environment.