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
Normal placenta contains fetal and maternal pa. Which is the MOST inner pa of placenta? 
Select and explain. 
A. Decidua basalis, B. Nitabuch layer, C. Cytotrophoblast, D. Syncytiotrophoblast
D: Syncytiotrophoblast
Answer: D: Syncytiotrophoblast 
Explanation: The placenta is limited internally (fetal aspect) by the amniotic membrane and chorionic plate; externally (maternal aspect) by the basal plate. Basal plate consists of following structures from outside inwards; Pa of the compact and spongy layer of the decidua basalis Nitabuch's layer of fibrinoid degeneration of the outer syncytiotrophoblast at the junction of the cytotrophoblastic shell and decidua Cytotrophoblastic shell Syncytiotrophoblast Ref: Textbook of Obstetrics by D C Dutta, 6th edition, Page 30.