This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
The antibodies that are seen in Grave's disease are- 
Select and explain. 
A. ANA, B. TSH receptor antibodies (TRAb), C. Thyroid peroxidase antibodies, D. Anti-T3 antibodies
B: TSH receptor antibodies (TRAb)
Answer: B: TSH receptor antibodies (TRAb) 
Explanation: Graves' disease is characterised by the production of IgG antibodies directed against the TSH receptors on the thyroid follicular cells which stimulate thyroid hormone production and proliferation of follicular cells. These antibodies are known as thyroid-stimulating immunoglobulins(TSI) or TSH receptor antibodies(TRAb). These can be detected in the serum of 80-95% of patients with Graves' disease. Reference : page 747-48Davidson's Principles and practice of Medicine 22nd edition