Passage: In 1238, Goryeo relented and sued for peace. The Mongols withdrew, in exchange for Goryeo's agreement to send the Royal Family as hostages. However, Goryeo sent an unrelated member of the Royal line. Incensed, the Mongols demanded to clear the seas of Korean ships, relocate the court to the mainland, the hand-over of anti-Mongol bureaucrats, and, again, the Royal family as hostages.  In response, Korea sent a distant princess and ten children of nobles.

Question: What were the Mongols's demands?
to clear the seas of Korean ships, relocate the court to the mainland, the hand-over of anti-Mongol bureaucrats, and, again, the Royal family as hostages