This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Rectum, Subject name: Surgery
[{'content': 'in rectal atresia - \nSelect and explain. \nA. Anus is normal, B. Rectovesical fistula present, C. It is low type of anorectal malformation, D. Rectovesical fistula is most common in males', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Anus is normal o Rectal atresia is classified as high type of anorectal malformation. In this defect, anal canal is normal but, ends proximally just below the level of pelvic floor whereas rectum ends below blindly above pelvic floor. This anomaly is rare and usually not associated with fistulous connection.Classification of Anorectal malformationsI HIGHAnorectal agenesis +- rectovaginal/rectoprostatic urethral fistula Rectal Atresia.II INTERMEDIATEAnorectal agenesis +- rectovaginal/recfobulbar urethral fistula Anal Agenesis.III LOWAnovestibular/Anocutaneous fistula (anteriorly displaced fistula) Anal stenosis.IV CLOACA", 'role': 'assistant'}]