In 1981, the <answer>MUSE</answer> system was demonstrated for the first time in the United States, using the same 5:3 aspect ratio as the Japanese system. Upon visiting a demonstration of <answer>MUSE</answer> in Washington, US President Ronald Reagan was impressed and officially declared it "a matter of national interest" to introduce HDTV to the US.
Which system was demonstrated in the US for the first time in 1981?
MUSE