This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urethra & Penis, Subject name: Surgery
[{'content': 'Which of the following changes would be most consistent with the diagnosis of choriocarcinoma? \nSelect and explain. \nA. Increased B-HCG, B. Increased alpha-fetoprotein (AFP), C. Increased thyroid-stimulating hormone (TSH), D. Decreased AFP', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Gestational trophoblastic disease may involve hydatidiform mole, choriocarcinoma, or placental trophoblastic tumor. Trophoblastic tissue produces B-HCG and thus B-HCG is elevated in all these conditions. AFP is increased in neural tube defect setting when screening at 15-18 weeks gestation. AFP may be decreased in Down syndrome.', 'role': 'assistant'}]