This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abdominal Radiography, Subject name: Radiology
Apple core appearance on barium enema is seen in? 
Select and explain. 
A. Carcinoma Colon, B. TB caecum, C. Crohns disease, D. Ulcerative colitis
A: Carcinoma Colon
Answer: A: Carcinoma Colon 
Explanation: Ans. (a) Carcinoma ColonRef: Bailey 26th ed. 170* On double contrast barium enema of the rectum and distal sigmoid colon demonstrates a typical annular constricting carcinoma of the colon with overhanging edges on both the proximal and distal margins forming a so called "apple-core" lesion.