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: Anaesthesia
[{'content': 'Heparin interferes with which of the following results of ABG \nSelect and explain. \nA. PO2, B. PCO2, C. ph, D. All', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. pH Heparin is strongest organic acid present in body, so it can decrease pH.', 'role': 'assistant'}]