Which of the following is not a cause of oropharyngeal carcinoma?

Ans. is 'a' i.e., Occupational exposure to hydrochloric acid Etiology of oropharyngeal carcinoma Tobacco in any form - cigarette smoking or chewing Heavy alcohol abuse Beetle nut chewing Plummer vinson syndrome, cirrhosis Syphilis Trauma Dental irritation Poor oral hygiene Occupational exposure to isopropyl alcohol, sulphuric acid and nickel HPV infection