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
[{'content': "The Lab investigation of a patient shows.↓T4, & ↑TSH. Which of the following is the most likely diagnosis - \nSelect and explain. \nA. Grave's disease, B. Hashimoto's disease, C. Pituitary failure, D. Hypothalamic failure", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]