This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypo Pigmentary Disorders, Subject name: Dental
[{'content': "Hypopigmented patches may be seen in: \nSelect and explain. \nA. Becker's nevus, B. Nevus anemicus, C. Nevus of Ota, D. Nevus of Ito", 'role': 'user'}, {'content': "Answer: B \nExplanation: Nevus anaemicus (NA) - Congenital disorder characterized by macules of varying size and shape that are paler than the surrounding skin and cannot be made red by trauma, cold, or heat. Paler area is due to the blood vessels within the area which are more sensitive to body's normal vasoconstricting chemicals. Hyperpigmentary disorders: Nevus of OTA Nevus of ITO Becker's Nevus", 'role': 'assistant'}]