<prompt> Quellung phenomenon is seen in:PneumococcusStreptococcusStaphylococcusHemophilus  <response>: Ans. is a i.e., Pneumococcus Ref: Ananthanarayan, 8the, p. 220, 9the, p. 223 A positive reaction shows clumping because of cross-linking of the antibodies and pneumococci. The halo effect around the pneumococci is apparent capsular swelling. A negative control would show no clumping or capsular swelling. 