question: Q:Which of the following statements correctly characterizes an autoimmune disease?? 
  A:T cells attack healthy body cells.;B:An aneurysm is a weakness in the wall of a blood vessel that causes it to balloon out. The vessel can rupture and cause a hemorrhage.;C:Several factors cause hypertension: smoking, being overweight, lack of physical activity, and too much salt in the diet.;D:Alzheimer's disease is caused by the buildup of plaque within the brain, causing brain cells to die.