This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Non communicable diseases, Subject name: Social & Preventive Medicine
Commonest carcinoma in men in tropical countries - 
Select and explain. 
A. Ca rectum, B. Ca oral cavity, C. Ca testis, D. Ca bladder
B: Ca oral cavity
Answer: B: Ca oral cavity 
Explanation: Oral cancer is one of the ten most common cancers in the world Mostly due to Tobacco Alcohol Precancerous state Cultural pattern Ref- Park&;s textbook of Preventive and Social Medicine 24th edition.