Federal investigators are asking witnesses whether former President Donald Trump showed off to aides and visitors a map he took with him when he left office that contains sensitive intelligence information, four people with knowledge of the matter said. The map has been just one focus of the broad Justice Department investigation into Trump’s handling of classified documents after he departed the White House. The nature of the map and the information it contained is not clear. But investigators have questioned a number of witnesses about it, according to the people with knowledge of the matter, as the special counsel...