MUMBAI (Reuters) -The rising popularity of U.S. dollar stablecoins will be an important phenomenon next year and could raise challenges for monetary policy globally, India's Chief Economic Adviser V. Anantha Nageswaran said on Wednesday. "The presence of a dollar stablecoin will bring with it its own challenges for monetary policy, monetary transmission and for seigniorage benefits of any country," Nageswaran said at an event in Mumbai. Seigniorage refers to the difference between the face value of money ...