This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Obstetrics, Subject name: Gynaecology & Obstetrics
[{'content': 'TRUE about Gestational Trophoblastic Disease is? \nSelect and explain. \nA. Most common site of metastasis is vagina, B. Presence of Lung metastasis classifies as stage 4 GTN, C. Liver metastasis carries a poor prognosis similar to brain metastasis, D. GTN following a term pregnancy has a better prognosis than that with previous molar pregnancy', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Most common site of metastasis in choriocarcinoma is lung, which is classified as stage 3. Brain and liver metastasis are stage 4 and carry poor prognosis GTN following term pregnancy carries worse prognosis than that following a molar pregnancy or an aboion', 'role': 'assistant'}]