Which of the following is not an autoimmune disease?

Due to genetic and other unknown reasons, the body attacks self-cells which results in damage to the body and is called auto-immune disease. Rheumatoid arthritis (joints), Psoriasis (scaly patches on the skin) and vitiligo(loss of melanocytes in the skin) are some of the auto-immune diseases.

Alzheimer's disease is not an autoimmune disease. Alzheimer's is an inherited progressive disease, where dementia symptoms gradually worsen over a number of years. In its early stages, memory loss is mild, but with late-stage Alzheimer's, individuals lose the ability to carry on a conversation and respond to their environment. It is thought to be caused by the abnormal build-up of proteins in and around brain cells. One of the proteins involved is called amyloid, deposits of which form plaques around brain cells.