Respuesta :
This is an example of gene flow.
In population genetics, gene flow (also known asgene migration) is the transfer of alleles or genes from one population to another. Migration into or out of a population may be responsible for a marked change in allele frequencies (the proportion of members carrying a particular variant of a gene).
The correct answer between all the choices given is the third choice or number 3. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.