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: Radiology
[{'content': 'Commonest mass in the middle mediastinum is – \nSelect and explain. \nA. Lipoma, B. Aneurysm, C. Lymph node mass, D. Congenital cysts', 'role': 'user'}, {'content': 'Answer: C \nExplanation: "Lymphadenopathy is by for the most common middle mediastinal mass".\n"The most common middle mediastinal mass is adenopathy".\n"Lymphadenopathy is the most common middle mediastinum mass".\xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0\xa0\n\nYou should keep in mind that, though, the most common middle mediastinal mass is lymph nodes enlargement, duplication congenital cysts (Bronchogenic cysts, esophageal duplication cysts) are the most common middle mediastinal masses in children.\n\nMost common anterior mediastinal mass \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0→ \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0Thymoma\nMost common middle mediastinal mass \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 → \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 Lymphadenopathy\nMost common middle mediastinal mass in children \xa0 →\xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0\xa0 Congenital duplication cysts\xa0\nMost common posterior mediastinal mass \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0→ \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 Neurogenic tumors\xa0\nOverall most common mediastinal mass \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0→ \xa0 \xa0 \xa0 \xa0 \xa0 \xa0\xa0\xa0\xa0Neurogenic tumors\n\xa0\xa0\nNote -\xa0Neurogenic tumors constitute 20% and thymomas constitute 19% of\xa0all\xa0the mediastinal masses.', 'role': 'assistant'}]