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': 'Intercavitatory radiotherapy is treatment modality for \nSelect and explain. \nA. Ca Cervix, B. Ca Oesophagus, C. Ca Stomach, D. Renal cell CA', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Intracavitary brachytherapy is used most commonly in patients with cancer cervix after radiation therapy has been completed.', 'role': 'assistant'}]