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': 'Which is not increased in pregnancy : \nSelect and explain. \nA. Vital capacity, B. Blood volume, C. Extracellular fluid, D. Weight', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Vital capacity', 'role': 'assistant'}]