This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
All are clinical features of myasthenia gravis, EXCEPT: 
Select and explain. 
A. Spontaneous remission, B. Absent deep tendon reflexes, C. Proximal muscle involvement, D. Worsen by exeion
B: Absent deep tendon reflexes
Answer: B: Absent deep tendon reflexes 
Explanation: Answer is B (Absent deep tendon reflexes): 'Despite the muscle weakness, deep tendon reflexes are preserved' -- Harrison 16th/2519; Harrison 17th/ 2673 'Suspect Myaesthenia gravis in a case of weakness with fatiguability, without loss of reflexes & impairment of sensations' -- Harrison Mvaesthenia Gravis : Review : Etiology : Autoimmune disorders mediated by specific Anti ACH receptor antibodies. Fundamental defect : Decrease in number of available ACH receptors at post synaptic muscle membrane. Age / Sex : All ages are affected Most prevalent in women in twenties/ thiies and men in fifties & sixties. Women are affected more frequently than menQ. (3 : 2) Features : Weakness : in characteristic distribution as elaborated below Fatiguability: Weakness increases on repeated use and may improve following rest or sleep A variable course marked by remissions and exacerbations (remissions are rarely complete or permanent) Association : Thymic abnormalities and Thymomas (Neoplastic) Autoimmune disorders : Rheumatoid Ahritis, SLE, Perenicious anemia, hypehyroidism, ulcerative colitis, polymyositis etc.