Final answer:
Damage to the brain stem can be fatal as it controls vital functions. Strokes due to blockage or breakage of arteries in the brain can lead to cell death and are a common cause of death.
Step-by-step explanation:
The brain structure most likely to cause death if damaged is the brain stem, which controls vital functions such as heart rate and breathing. A stroke or cerebrovascular accident occurring in this area can lead to immediate death due to the cessation of these essential functions. Strokes result from a blockage or breakage of arteries leading to the brain, causing a lack of blood flow and the death of brain cells. Traumatic brain injuries, including damage to the brain stem, are among the leading causes of death, particularly from falls, vehicle accidents, or blunt trauma.