<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 2-year-old male is brought to his pediatrician by his mother because of abdominal pain and blood in the stool. Scintigraphy reveals uptake in the right lower quadrant of the abdomen. Persistence of which of the following structures is the most likely cause of this patients symptoms?? A: Urachus, B: Omphalomesenteric duct, C: Paramesonephric duct, D: Allantois, E: Ureteric bud,  <response>: This is a question about a 2-year-old male with abdominal pain, bloody stool, and uptake in the right lower quadrant on scintigraphy. The question is asking about the most likely persistent embryonic structure that could be causing these symptoms.Based on the location of the uptake in the right lower quadrant, this likely indicates some sort of issue in the ileocecal region where the small intestine meets the large intestine. The most common persistent embryonic structures that can cause symptoms in this area are remnants of the omphalomesenteric duct or vitelline duct. These ducts normally regress during embryonic development but can sometimes persist and cause problems later in life.Choices A, C, D and E can all be ruled out as they do not relate to embryonic structures in the ileocecal region. Only choice B, the omphalomesenteric duct, fits with the clinical presentation described.B: Omphalomesenteric duct 