Which type of stroke is caused by a sudden blockage of a blood vessel in the brain?

The type of stroke caused by a sudden blockage of a blood vessel in the brain is an ischemic cerebrovascular accident (CVA). This occurs when an artery supplying blood to the brain becomes obstructed, reducing blood flow and oxygen to brain tissue. This blockage can result from various factors, including blood clots or fatty deposits, which lead to the ischemic process.

In contrast, a hemorrhagic CVA involves the rupture of a blood vessel, causing bleeding in the brain, rather than a blockage. A Transient Ischemic Attack (TIA) is characterized by temporary symptoms of weakness or numbness that resolve within 24 hours and are due to temporary reductions in blood flow, but it does not result in the permanent damage associated with an ischemic stroke. Subarachnoid hemorrhage specifically refers to bleeding in the space surrounding the brain, typically due to a ruptured aneurysm, rather than blockage of a vessel. Therefore, the correct answer identifies the mechanism of an ischemic stroke as a critical factor in understanding this medical condition.