2. To people who believed in the Mandate of Heaven, when was it all right to overthrow an emperor? never at any time
b
when he ruled badly
c
when he became unpopular
d
when citizens wanted a change

when he ruled badly so b

Explanation:

i say this because a emperor in order to become one you need the blessing from heaven in ther religion so what im saying is if they ruled badly under the will and grace of heaven and were bad they were thrown of the dynasty no longer emperor.

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