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
Piebaldism refers to: 
Select and explain. 
A. Androgenic alopecia, B. Idiopathic guttate hypomelanosis, C. Association of vitiligo with white forelock, D. Acquired condition
C: Association of vitiligo with white forelock
Answer: C: Association of vitiligo with white forelock 
Explanation: Piebaldism Rare AD disorder of melanocyte development characterized by congenital white forelock and multiple symmetrical hypopigmented or depigmented macules. Etiology: Absence of melanocytes in affected skin and hair follicles as a result of mutations of the KIT proto-oncogene. Symmetric involvement of central forehead, ventral trunk, and mid regions of upper and lower extremities. Idiopathic Guttate Hypomelanosis (IGH) is a benign and asymptomatic skin manifestation characterized as diffuse hypopigmented macules, or white spots.