This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Anatomy
[{'content': 'During active labor cervical dilatation per hour in primi is \nSelect and explain. \nA. 1.2 cm, B. 1.5 cm, C. 1.7 cm, D. 2 cm', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Active labor: Cervix dilatation to atleast >6 cm Regular uterine contractions are present Rate of dilatation is atleast 1.2 cm/hr for nulliparous and 1.5cm/ hr for parous women', 'role': 'assistant'}]