What type of stroke is most likely to present with a sudden and severe headache?

A sudden and severe headache is a classic symptom associated with a hemorrhagic stroke. This type of stroke occurs when a blood vessel in the brain ruptures, leading to bleeding in or around the brain. The sudden onset of a severe headache, often described as a "thunderclap headache," is due to the irritation of brain tissues and the increase in intracranial pressure caused by the bleeding.

In contrast, ischemic strokes, which include thrombotic and embolic types, typically present with neurological deficits such as weakness, numbness, or difficulties with speech, rather than with a sudden severe headache. These types of strokes result from a blockage of blood flow to the brain, which can lead to gradual onset of symptoms rather than an acute headache.

Therefore, the presence of a sudden and severe headache directs suspicion toward a hemorrhagic stroke, making it the correct choice.