The US Federal Trade Commission has sued to block the merger between grocery-store chains Kroger Co. and Albertsons Cos. Inc.. According to FTC, the merger would stifle competition, raise grocery prices, and harm workers and product quality. Nine attorneys general — from Arizona, California, Illinois, Maryland, Nevada, New Mexico, Oregon, Wyoming and the District of Columbia — are also joining the complaint against the $24.6 billion deal, which the FTC said would be the biggest supermarket me...