The general Genghis Khan left as his viceroy in North China was Muqali.
Muqali was a trusted Jalair commander who became one of Genghis Khan’s most capable deputies during the Mongol invasion of the Jin dynasty. When Genghis Khan turned west to fight the Khwarazmian Empire, he left Muqali in charge of the northern Chinese front.
Muqali received unusually broad autonomy and the title of gui ong, or kuo-wang, along with the Chinese title taishi. He continued the war against Jin with a relatively small Mongol force supported by local auxiliaries and conquered or subdued large areas of northern China.
The other options were also major Mongol commanders, which makes this question easy to confuse. Bo’orchu was an early companion and senior commander, Jebe was a celebrated cavalry general, and Subutai became one of the empire’s greatest strategists. None held Muqali’s specific viceroyal role in North China under Genghis Khan.