This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Vimal, a 70 years old male presents with a h/o lower GI bleed for last 6 months. Sigmoidoscopic examination shows a mass, of 4 cms about 3.5 cms above the anal verge. The treatment of choice is - 
Select and explain. 
A. Colostomy, B. Anterior resection, C. Abdominoperineal resection, D. Defunctioning anastomosis
C: Abdominoperineal resection
Answer: C: Abdominoperineal resection 
Explanation: None