Which of the following circumstances contributed to the decline of the han dynasty?
a. establishment of state religion
b. insufficient tax revenue
c. distraction caused by natural disasters
d. internal peasant revolts
e. attacks by powerful warlords

The answers are
C. Distraction caused by natural disasters
D. Internal peasant revolts
E. Attacks by powerful warlords
All of these things make the government of han dynasty have to spent a lot of resources in order to handle these problems. But since all of these circumtances happened at the same time, the Han dynasty was unable to keep up and eventually led to its fell.