Final answer:
The newly discovered monkey population named Cercopithecus albigena would be most closely related to Cercopithecus hamlyni, since they both share the genus Cercopithecus, indicating a closer evolutionary link compared to species from different genera.
Step-by-step explanation:
If a newly discovered monkey population was named Cercopithecus albigena, it would be most closely related to B.Cercopithecus hamlyni. This is because the genus name 'Cercopithecus' indicates that both species belong to the same genus and, thus, share a more recent common ancestor in comparison with species from different genera. The other options given, such as Cercocebus and Parapithecus, belong to different genera, indicating a less close relationship.
It is important to note that monkeys are classified into two major groups: New World monkeys (Platyrrhini) with broad noses and Old World monkeys (Catarrhini) with narrow, downward-pointed noses. The genus Cercopithecus is an Old World monkey, distinct from New World monkeys. Moreover, Old World monkeys like Cercopithecus are part of the cercopithecoidea superfamily, which does not include apes. Apes, such as gorillas, orangutans, and chimpanzees, belong to the hominoidea superfamily and are more closely related to humans than any species of monkeys.