Correct Option: B

Kublai Khan (1215-1294) was the founder of the Yuan Dynasty. After defeating his younger brother Alibuge who intended to grab the crown in 1264, Kublai Khan took the throne, with “Zhiyuan” as the reign title. Afterwards, he moved the capital to Yanjing (the current Beijing) and renamed it “Dadu”. In 1271, Kublai Khan set “Yuan” as the official name of the nation and then confirmed Dadu as the capital in 1272.