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: Biochemistry
[{'content': "At isoelectric pH proteina) Have Net charge '0'b) Are positively chargedc) Are negatively chargedd) Don't migrate \nSelect and explain. \nA. ad, B. c, C. ac, D. ab", 'role': 'user'}, {'content': 'Answer: A \nExplanation: its isoelectric pH, amino acid bears no net charge and does not move (migrate) in an electric field.', 'role': 'assistant'}]