Which foreign group ruled China during the Yuan dynasty?

Yuan dynasty, Wade-Giles romanization Yüan, also called Mongol dynasty, dynasty established by Mongol nomads that ruled portions and eventually all of China from the early 13th century to 1368.

following type of cultural development caused people to want and buy new products on the market :

seeing as no choices were provided, i'll do my best to answer it from knowledge.

job specialization promotes work ethic to the person doing the job. he/she may be strong in the arms and able to lift things, specializing him/her in a job where you lift and carry.