B

Reasoning: Melanocytes located at the dermo-epidermal junction are the cells that can acquire atypia and evolve into melanoma; therefore junctional (or junctional-component) nevi carry the highest malignant potential among common benign skin lesions. Studies of early melanomas show that when a pre-existing nevus is present it is most often one with active junctional nests rather than an intradermal nevus, and far more often than non-melanocytic lesions such as lichen planus or papilloma [Stolz 1989, PMID 2643457]. Intradermal nevi, cutaneous papillomas, and cutaneous lichen planus very rarely undergo malignant change.