Answer is A (High fiber diet): Epidemiologic, case control and animal studies suggest that dietary fibers are protective against the development of colon cancer Fat is primarily related as a 'promoting' agent such that high fat in diet is believed to promote carcinogenesis. Low Fat has not been shown to have a 'protective' role in carcinogenesis although it may reduce the incidence of colonic carcinoma indirectly by reducing a 'promoting effect'. Low selenium is 'possibly related' as a promoting agent Low Protein has not been mentioned in relation to carcinogenesis in the colon.