This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
[{'content': 'Gemcitabine is effective in \nSelect and explain. \nA. Head and neck cancers, B. Pancreatic cancer, C. Small lung cell cancer, D. Soft tissue sarcoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Refer Katzung 10th/891 Gemcitabine is an Antimetabolite that is th^ drug of choice for pancreatic cancers', 'role': 'assistant'}]