Which World War II battleship was the most advanced?
Short answerProbably an Iowa-class ship, with King George V a contender and Vanguard too late for wartime service.
NotesOne of the Iowa-class ships is favored because they were the newest major battleships to enter wartime service. King George V remains a plausible contender on capability and design grounds. Vanguard is more modern in some respects but arrived too late for operational World War II service. The answer makes service date part of what counts as the most advanced wartime ship.