This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
[{'content': 'All of the following modalities can be used for in situ ablation of liver secondaries, except \nSelect and explain. \nA. Ultrasonic waves, B. Alcohol, C. Radio frequency, D. Cyrotherapy', 'role': 'user'}, {'content': "Answer: A \nExplanation: Local (in situ) ablative therapies for liver secondaries Cryotherapy - in situ destruction of tissues by freeze-thaw process. Radio frequency ablation - a probe inseed into the middle of the tumor emits radiofrequency waves from its tip, which heats the surrounding tissue, resulting in coagulative necrosis. Percutaneous ethanol injection Trans catheter chemoembolization Ref : Devita's Cancer: Principles & Practice, 7/e, p 2362", 'role': 'assistant'}]