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: Surgery
Most common origin of melanoma is from 
Select and explain. 
A. Junctional melanocytes, B. Epidermal cells, C. Basal cells, D. Follicular cells
A: Junctional melanocytes
Answer: A: Junctional melanocytes 
Explanation: Sabiston (16/e) writes -
"Melanoma is a neoplastic disorder produced by malignant transformation of the normal melanocytes. Melanocytes are the cells responsible for the production of the pigment melanin.
During the first trimester of fetal life precursor melanocytes arise in the neural crest. As the fetus develops, these cells migrate to areas such as the skin, meninges, mucous membranes, upper esophagus and eyes.
In each of the these locations, melanocytes have demonstrated a potential for malignant transformation, but the site most commonly associated with melanocytic transformation is the skin, where melanocytes reside at the dermal/epidermal junction".