This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of the female genital tract, Subject name: Gynaecology & Obstetrics
For hormonal study, sample should be taken from which wall of vagina 
Select and explain. 
A. Anterior, B. Posterior, C. Lateral, D. Any wall
C: Lateral
Answer: C: Lateral 
Explanation: Lateral walls of vaginaThe upper one third is related with the pelvic cellular tissue at the base of broad ligament in which ureter and uterine aery lie approximately 2cm from lateral fornicesThe middle third is blended with levator ani The lower third is related to bulbocavernosus muscle, vestibular bulbs and Baholin glands.Ref: D.C. Dutta&;s Textbook of Gynaecology, 6th edition, page no: 5