This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Gynaecology & Obstetrics
[{'content': 'Ideally, traction during vacuum extraction should be applied in which of the following manner? \nSelect and explain. \nA. Continously, B. Intermittently with cycles of 20seconds of traction followed by 1minute of rest, C. Intermittently and with contractions, D. Intermittently and between contraction', 'role': 'user'}, {'content': "Answer: C \nExplanation: After the vacuum is applied, Effo should be intermittent and coordinated with maternal expulsive effos and contractions(Ref: William's Obstetrics; 25th edition)", 'role': 'assistant'}]