Question: Who is the game designer born in 1950 who is best known for his work on materials for the "Dungeons & Drangon fantasy role-playing game?
Sentence (from "Frank Mentzer"): Jacob Franklin "Frank" Mentzer III (born in 1950), is an American fantasy author and game designer best known for his work on early materials for the "Dungeons & Dragons" (D&D) fantasy role-playing game.
Relevant evidence: Yes