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
Which of the following is the commonest site for Ca colon? 
Select and explain. 
A. Caecum, B. Sigmoid colon, C. Ascending colon, D. Transverse colon
B: Sigmoid colon
Answer: B: Sigmoid colon 
Explanation: The frequency is sigmoid colon > caecum > transverse colon > ascending colon.