This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Structure of DNA, Subject name: Biochemistry
[{'content': 'At the physiological pH the DNA molecules are \nSelect and explain. \nA. Positively charged, B. Negatively charged, C. Neutral, D. Amphipathic', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is \'b\' i.e. Negatively charged DNA molecules are negatively charged, this is evident as it is stained by a cationic (positively charged) dye.Read the following lines for Ronald Hoffman Hematology:"Anionic cellular elements (nuclear DNA) reacts with cationic dye (Methylene blue)"', 'role': 'assistant'}]