Which of the following best describes the autoimmune condition ‘Rheumatoid Arthritis’

A. The articular cartilage in a joint has completely worn away causing bones to ‘rub’ against each other causing pain

B. Bones have become hollow and brittle, allowing them to fracture easily

C. It is an overuse condition which can affect any synovial joint in the body

D. Inflammation of and thickening of the joint casual surrounding synovial joints