<prompt> The test likely to help in diagnosis of a patient who presents with an itchy annular plaque on the face is:Grams stainPotassium hydroxide mountTissue smearWoods lamp examination  <response>: B i.e. KOH mount Trichophyton rubrum is most common cause of tinea corporis body, t. cruris, t. pedis, t. manuum t.unguiumQ. Diagnosis is made by KOH wet mount. 