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
A 55 year old male, working as a hotel cook, has four dependent family members. He has been diagnosed with an early stage squamous cell cancer of anal canal. He has more than 60% chance of cure. The BEST treatment option is: 
Select and explain. 
A. Abdominoperineal resection, B. Combined surgery and radiotherapy, C. Combined chemotherapy and radiotherapy, D. Chemotherapy alone
C: Combined chemotherapy and radiotherapy
Answer: C: Combined chemotherapy and radiotherapy 
Explanation: "Nigro regimen is referred to combined chemotherapy and radiotherapy used for primary treatment of malignant tumors of the anal canal". Ref: Bailey & Love 25/e, page 1269; Schwaz 9/e, Page 1053.