Option 1 -> Highlight means to emphasize or draw attention to something, not to assume or propose.
Option 2 -> Disprove means to prove something is false, which is the opposite of postulating.
Option 3 -> Refute means to prove a statement wrong or false, also contrary to postulating.
Option 4 -> Hypothesize means to propose an assumption or theory as a basis for reasoning, which closely aligns with postulate.
Hence, Option 4: Hypothesize -> "Postulate" means to suggest or assume something as true for the basis of reasoning or argument, which is essentially the same as hypothesizing. Both words involve proposing an idea or assumption that needs to be examined or tested -> correct