<prompt> Underlying pathology of Nevus anemicus is:Autoimmune destruction of melanocytesArrest of migration of melanocytesAbnormal vasoconstrictionDefect in tyrosinase enzyme  <response>: Nevus anemicus presents as a localized area of skin blanching and hypopigmentation because of abnormal vasoconstriction due to increased sensitivity of blood vessels to catecholamines. 