Final answer:
The correct answer is C. The fossil primate Biretta is considered an early anthropoid because it had dental features characteristic of early anthropoids, with small front teeth and very large molars. This indicates a closer relation to later anthropoids rather than non-anthropoid primates.
Step-by-step explanation:
The Northern African fossil primate Biretta is considered to be an early anthropoid primarily because it possessed dental features characteristic of early anthropoids, including small front teeth such as canines and incisors, and very large molars relative to other primate species. This dental pattern is indicative of later anthropoids and is distinct from the teeth of non-anthropoid primates.
The development of dentition in early hominins, such as Australopithecus, showed a trend towards smaller canines and molars compared to apes, but these were larger than those of modern humans. Australopithecus afarensis, often known through the fossil named 'Lucy,' had a brain size comparable to that of a modern chimpanzee and also demonstrated bipedalism, which is a key feature of later anthropoids and hominins.