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: Gynaecology & Obstetrics
[{'content': 'Type IIIB Endometrial cancer (FIGO) is \nSelect and explain. \nA. Endometrial cancer invading cervical stroma, B. Endometrial cancer with vaginal involvment, C. Endometrial cancer involving uterine adnexa, D. Endometrial cancer invading Pelvic lymph nodes', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]