<prompt> Which of the following are bacterial infection of skin?Pyoderma gangrenosumPiedraImpetigo contagiosaImpetigo herpetiformis  <response>: C i.e. Imetigo contagiosaPiedra is a fungal infection of hair. Pyoderma gangrenosum is a rare, serious ulcerative disorder that is often dt serious underlying systemic disease eg ulcerative colitis, chrons disease, rheumatoid ahritis or myeloma etc. Impetigo herpetiformis is the synonym of generalized pustular psoriasis of pregnancy. 