Answer is option D) Rheumatoid arthritis ...
Autoimmune diseases occur when the body’s immune system, mistakenly attacks own healthy cells.Rheumatoid arthritis  is a long-term autoimmune disorder that primarily affects joints.It typically results in warm, swollen, and painful joints.In rheumatoid arthritis, immune system mistakenly sends antibodies to the lining of the joints, where they attack the tissue surrounding the joint.....

An autoimmune disease:

An autoimmune disease is a condition in which the immune system mistakenly attacks and destroys healthy body tissues. It occurs when the immune system, which is designed to protect the body from foreign invaders such as bacteria and viruses, becomes overactive and targets its own cells and tissues.

Rheumatoid arthritis:

Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects the joints. It causes inflammation, pain, stiffness, and swelling in the joints, often leading to joint deformity and disability over time. RA can also affect other parts of the body, including the skin, eyes, lungs, heart, and blood vessels.

Key points about rheumatoid arthritis:

1. Chronic inflammation: Rheumatoid arthritis is characterized by chronic inflammation in the synovium, the lining of the joints. This inflammation leads to the destruction of cartilage and bone, causing joint pain and deformity.

2. Autoimmune nature: In rheumatoid arthritis, the immune system mistakenly attacks the synovium, triggering an immune response that leads to inflammation. The exact cause of this autoimmune response is not fully understood, but a combination of genetic and environmental factors is believed to play a role.

3. Joint involvement: Rheumatoid arthritis typically affects the small joints of the hands, wrists, and feet symmetrically. However, it can also involve larger joints such as the knees, elbows, and shoulders. The joints may become swollen, tender, and warm to the touch.

4. Extra-articular manifestations: Rheumatoid arthritis can also cause inflammation in other organs and tissues, known as extra-articular manifestations. These can include nodules under the skin, lung inflammation (pulmonary fibrosis), heart inflammation (pericarditis), and blood vessel inflammation (vasculitis).

5. Treatment options: The goal of treatment for rheumatoid arthritis is to reduce inflammation, relieve pain, and preserve joint function. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), disease-modifying antirheumatic drugs (DMARDs), and biologic therapies are commonly used. Physical therapy, exercise, and lifestyle modifications can also help manage symptoms and improve quality of life.

Conclusion:

Rheumatoid arthritis is an autoimmune disease characterized by chronic inflammation in the joints. It can cause pain, swelling, and joint deformity. Early diagnosis and treatment are essential to prevent joint damage and disability.