Based on the model of speciation presented, which of the following describes the most likely consequence to the populations over time? Hybrid individuals are less likely to pass their genetic information on to subsequent generations. A Hybrid individuals living together are physically unable to mate with each other. B Geographically isolated populations gradually acquire similar heritable traits. C Differences between hybrid individuals of a species disappear over time.

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?