The most accurate impact that Mongol leaders Genghis Khan and Kublai Khan had on Europe from the options provided is:
D. They introduced Eastern culture and literature to Europeans.
While Genghis Khan and Kublai Khan were not primarily focused on spreading culture to Europe, the Mongol Empire facilitated trade and cultural exchange between East and West, particularly through the Silk Road. This exchange included not only goods but also ideas, technology, and literature, influencing European societies in various ways.
Option A is incorrect because while there were interactions, the Mongols did not primarily spread Christianity in Europe. Option B is partially true regarding warfare techniques but not as significant or direct as cultural exchange. Option C is misleading; while there were raids, the more lasting impact was not destructive but rather through interaction and trade.