Final answer:
The Orangutan is the primate most closely related to the Gibbon.
Step-by-step explanation:
The primate that is more closely related to the Gibbon is the Orangutan. The Orangutan is one of the four living genera in the family Hominidae, which also includes chimpanzees, gorillas, and humans. Orangutans share certain features and genetic similarities with Gibbons, indicating a closer evolutionary relationship.