Final answer:
The most common onset of intracerebral vasospasm occurs within 48 hours after the ruptured intracranial aneurysm.
Step-by-step explanation:
The most common onset of intracerebral vasospasm occurs within 48 hours after the ruptured intracranial aneurysm. Intracerebral vasospasm is a constriction of the blood vessels in the brain that can occur after a ruptured intracranial aneurysm. This constriction can lead to reduced blood flow to the brain, potentially causing further damage or complications.