Answer : 4. "All of the above"
Explanation :

Answer: D) All of the above Explanation: Vitiligo is a condition in which the skin loses its pigment cells (melanocytes). This can result in discolored patches in different areas of the body, including the skin, hair, retina and mucous membranes. Many disorders have been linked to vitiligo. They are:: Hashimoto thyroiditis, Graves disease, Addison disease and diabetes mellitus, alopecia areata, pernicious anemia, inflammatory bowel disease, psoriasis, and autoimmune polyglandular syndrome.