I do not know what list of quality gurus you have been given to chose from. However, the most likely answer to this is William Edwards Deming, better known as Edwards Deming.
Deming is one of the most famous quality gurus in history. He is most often associated with the Total Quality Management system that helped to make Japan's economy boom in the years after WWII. Deming first went to Japan during the years of the American occupation. While there, he was asked by General MacArthur to help rebuild the Japanese economy.
Therefore, Deming is the most likely answer to this question.
Here is the list I was refering to: Deming, Juran, Crosby, Feigenbaum, Harrington, Ishikawa, Shewhart, Shingo, Taylor, and Taguchi. I was just curious if there is any information to link MacArthur to these gentlemen.