Beta phage is seen in -
Ans. is 'b' i.e., Corynebacterium diphtheriae o The toxigenicity of the diphtheria bacilli depends on the presence in it of corynephages (tox +). Nontoxigenic strains may be rendered toxigenic by infecting them with beta phage or some other larger phage. This is known as lysogenic conversion or phage conversion.
Bacillus anthracis
Corynebacterium diphtheriae
Clostridium botulinum
Peptostreptococci
Corynebacterium