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: Medicine
[{'content': 'In hepatic encephalopathy the EEG shows-a) a - activity wavesb) a (delta) - wavesc) e (theta) - wavesd) Rapid a - waves \nSelect and explain. \nA. bc, B. c, C. ac, D. ad', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]