Answer:
Autoimmune theory
Explanation:
Alzheimer's disease is the most common type of neurocognitive disorder, which usually occurs after the age of sixty-five and is characterized mainly by memory impairment.
The autoimmune theory suggests that <u>the immune system is prearranged so that it becomes unable to identify the body's proteins from foreign ones</u>. As a result, the immune system attacks its own cells.
Answer: Marina Trench
Explanation: The Mariana Trench stretches 2,500 kilometers (1,500 miles) in an arc that is edged by islands such as Guam and Saipan. Its deepest point is known as the Challenger Deep.
