This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Skin
Blaschko's lines refers to lines of: 
Select and explain. 
A. Melanocyte migration, B. Ectodermal cell migration, C. Mesodermal cell migration, D. Endodermal cell migration
B: Ectodermal cell migration
Answer: B: Ectodermal cell migration 
Explanation: Blaschko's lines are characteristic of mosaic conditions of the epidermis and probably represent the routes of ectodermal cell migration from the neural crest. Ref: Rook's textbook of dermatology, 8th edition, Pg 18.4.