The correct answer is option 1, Richard Nixon. In 1972, Richard Nixon, the 37th President of the United States, visited China to strengthen diplomatic ties between the two countries. This visit was a significant milestone in U.S.-China relations as it marked the first time a U.S. President had visited China since the country`s communist revolution in 1949. The visit led to the signing of the Shanghai Communique, in which both countries agreed to normalize relations and enhance cooperation. This visit was seen as a major step in thawing the Cold War tensions between the United States and China and opened up opportunities for further engagement and cooperation between the two nations.