Which of the following primates was more like an ape?

The correct option is Dryopithecus.

To understand why this is correct, we can look at the evolutionary history and characteristics of the primates listed in the options:
1. Dryopithecus: This genus of extinct apes lived during the Miocene epoch. Fossil evidence indicates that Dryopithecus was highly ape-like. They had a semi-erect posture, relatively long arms compared to their legs, and a brain size and skeletal structure that closely resembled modern apes (like chimpanzees and gorillas). They were primarily arboreal (tree-dwelling) and walked on all fours (quadrupedal).
2. Ramapithecus: Living later in the Miocene epoch, Ramapithecus walked more erectly and had dentition (teeth structure) that showed characteristics more transitional towards hominids (human ancestors), making them more human-like than Dryopithecus.
3. Australopithecines: These are early hominids that lived during the Plio-Pleistocene era. They exhibited bipedalism (walking on two legs) and had teeth that were more human-like, marking a significant evolutionary step away from apes.
4. Homo erectus: This is a direct ancestor of modern humans (Homo sapiens) with a fully upright posture, large brain capacity, and skeleton very similar to modern humans, showing almost no ape-like skeletal features.

Therefore, among the given choices, Dryopithecus is the primate that was most ape-like in its anatomy and behavior.