Which statement most accurately describes Rheumatoid arthritis?

A. A rapid severe systemic hypersensitivity reaction that may compromise airway, breathing or circulation. B. A chronic systemic autoimmune inflammatory arthritis typically affecting small joints symmetrically. C. Obstruction of pulmonary arteries, commonly by thrombus originating in deep veins. D. A state of deficient thyroid hormone action that may cause fatigue, weight gain and bradycardia.