This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Obstetrical Anatomy, Subject name: Gynaecology & Obstetrics
[{'content': 'Fertilization most commonly occurs at: \nSelect and explain. \nA. Ampulla, B. Interstitium, C. Isthmus, D. Uterine cavity', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. Ampulla* Fertilization is the process of fusion of the spermatozoon with the mature ovum.* Almost always, fertilization occurs in the ampullary part of the uterine tube.', 'role': 'assistant'}]