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': 'Reactivation of TB affects \nSelect and explain. \nA. Anterior segment of upper Lobe, B. Apical and posterior segments of  upper Lobe, C. Posterior segments of  lower Lobe, D. Posterior and inferior segments of lower lobe', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Reactivation of TB tends to involve apical and\xa0\xa0posterior segments of\xa0 upper Lobe and Superior segments of lower lobe.', 'role': 'assistant'}]