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: Gynaecology & Obstetrics
[{'content': 'Fetal scalp blood pH less than _ is abnormal : \nSelect and explain. \nA. 7.25, B. 7.3, C. 7.35, D. 7.4', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 7.25', 'role': 'assistant'}]