<prompt> Streptococci causing dental caries:Streptococci equisimilisStreptococci mutansStreptococci pneumoniaeStreptococci bovis  <response>: Ans. b Streptococci mutans S. mutans: It is member of viridans streptococci a-hemolytic which is pa of the normal flora of the oral cavity. It assumes bacillary form in acid environment. Can synthesize acid and large polysaccharide adhesive dextran or levan from sucrose. 