<prompt> All of the following are true about Chickenpox except:Incubation period can range from 10-21 days.Subclinical varicella is rareSimultaneous presence of lesions in various stages of evolution is characteristicUmbilicated vesicles are the earliest lesions to appear  <response>: d. Umbilicated vesicles are the earliest lesions to appearRef: Nelson 20e p1580-1581Initial exanthem in Chicken pox consists of pruritic erythematous macules that evolve through papular stage to form clear, fluid- filled vesicles. Clouding umbilication of the lesions begin in 24-48 hr.Simultaneous presence of lesions in various stages of evolution is characteristic of varicella.Distribution of rash is predominantly centripetal with greatest concentration on trunk. 