A population of deer is separated by an emerging volcano. The two populations come back into contact 200 years later, but are incapable of breeding. Which of the following best describes the process that occurred?

The volcano geographically isolated the deer populations, preventing them from breeding with each other. Over time, they became reproductively incompatible, so they are now separate species. This process is speciation; adaptation and the forms of selection listed do not specifically describe the formation of a new species.

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