This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abnormal labor, Subject name: Gynaecology & Obstetrics
The following statements are related to occipitoposterior except 
Select and explain. 
A. malrotation of occiput may cause occipitosacral arrest, B. 10% cases are associated with anthropoid or android pelvis, C. Incomplete forward rotation of occiput may cause deep transverse arrest, D. Nonrotation of occiput may cause are associated
B: 10% cases are associated with anthropoid or android pelvis
Answer: B: 10% cases are associated with anthropoid or android pelvis 
Explanation: Occipitoposterior position The occiput is in the posterior segment of pelvis ,over lying the sacroiliac joint or the sacrum.Occipitoposterior position is responsible for most cases of prolonged labour and second stage delay and is the most common cause of a mobile head at term (refer pgno:365 Sheila textbook of obstetrics 2 nd edition)