Answer:
The evolutionary process at work is best described by option B. gene flow
Step-by-step explanation:
Gene flow also known as migration is any movement of individuals, and/or the genetic material they carry, from one population to another. If gene versions are carried to a population where those gene versions previously did not exist, gene flow can be a very important source of genetic variation. In this case, the nearby population migrates to the mole population. The diagram is a good description of the Gene flow process.