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: Social & Preventive Medicine
[{'content': 'Semi essential amino acids are \nSelect and explain. \nA. Tryptophan, Tyrosine, B. Histidine, Arginine, C. Leucine, Lysine, D. Phenylalanine, Valine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]