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: Gynaecology & Obstetrics
Which of the following factor influence the progress of labor? 
Select and explain. 
A. Parity, B. BMI, C. Fetal position, D. All the above
D: All the above
Answer: D: All the above 
Explanation: Factors effecting the progress of labour : Parity of female CPD BMI Gestational age Fetal sex Twin pregnancy Ref: Fernando Arias 4e pg 338.