Why was china not controlled by dynastic rulers

From at least 1766BCE to the twentieth century of the Common Era, China was ruled by dynasties. A dynasty is a family that passes control from one generation to the next. A dynasty does not have to last for a long time.  One Chinese dynasty lasted more than 800 years while another lasted only fifteen years.

The ancient Chinese believed their ancestors in heaven had chosen their leaders. They called this the Mandate of Heaven. The Chinese people often rebelled against a weak leader if they believed he had lost the Mandate of Heaven.

answer; (d) all of the above; 100%