Which of the following fictional characters is a wizard?

Gandalf is a protagonist in J. R. R. Tolkien's novels The Hobbit and The Lord of the Rings. He is a wizard, one of the Istari order, and the leader of the Fellowship of the Ring. Tolkien took the name "Gandalf" from the Old Norse "Catalogue of Dwarves" (Dvergatal) in the Völuspá. As a wizard and the bearer of one of the Three Rings, Gandalf has great power but works mostly by encouraging and persuading. He sets out as Gandalf the Grey, possessing great knowledge and traveling continually.

Source: Wikipedia