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
Prognosis for carcinoma rectum is best assessed by - 
Select and explain. 
A. Site of tumour, B. Histological grading, C. Size of tumours, D. Duration of the symptoms
B: Histological grading
Answer: B: Histological grading 
Explanation: No effect on Prognosis: Tumor size and duration of symptoms.
Tumor size and configuration (endophytic, exophytic, annular) do not carry any prognostic significance in colorectal carcinoma.