This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast, Subject name: Pathology
[{'content': 'Myasthenia gravis is associated with \nSelect and explain. \nA. Thymoma, B. Thymic carcinoma, C. Thymic hyperplasia, D. Lymphoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Some 60%of Myasthenia gravis are associated with a peculiar reactive hyperplasia of intrathymic B cells and another 20%are associated with thymoma, a tumor of thymic epithelial cells. Robbins basic pathology 9th edition page no 800,heading =Myasthenia gravis Option 4 is correct', 'role': 'assistant'}]