Question: Which professional American football team is the only franchise to win championships while representing three different cities and was the team that Jack Youngblood played for?
Sentence (from "Jack Youngblood"): Herbert Jackson Youngblood III (born January 26, 1950) is an American former college and professional football player who was a defensive end for the Los Angeles Rams of the National Football League (NFL) for fourteen seasons during the 1970s and 1980s.
Relevant evidence: Yes