In "Game of Thrones," what is the name of Eddard Stark's bastard son?

In "Game of Thrones," Eddard Stark's bastard son is named Jon Snow. This character is central to the story and represents themes of identity and belonging, as he struggles with the stigma of being a bastard in a society that values noble lineage. Jon is raised at Winterfell alongside Eddard's legitimate children, which adds to the complexity of his character and his relationships. His journey throughout the series includes discovering the truth about his parentage and grappling with his role within the larger conflicts of Westeros.

The other characters listed do not fit the description of Eddard Stark's illegitimate son. Robb Stark and Bran Stark are Eddard's legitimate sons, while Tyrion Lannister is a member of a rival family and does not share any blood relation with the Stark family. This context highlights why Jon Snow is the correct answer.