<prompt> certain strains of Streptococcus mutansa have been proved to be the cause of human dental caries by means of control studiesb depend for their cariogenicity on the production of insoluble polysaccharidesc cause dental caries by the production of lactic and other acids from fermentation of sugard are a cause of infective endocarditise Will induce smooth surface caries in quotesa is false bcde is truea b is false c d e is truea b c is false d e is trueabcd is false e is true  <response>: Strep. mutans may be an important organism but not the only one, but controlled studies in humans cannot conceivably be carried out 