The Han Dynasty:

a) is the earliest Chinese dynasty about which substantial information is available
b) began and ended before 300 B.C., when China already was a well-organized state
c) was a pivotal and formative period in Chinese history, when the Chinese sphere of influence was enlarged, land reform occurred, and external trade commenced
d) is another name for the regime of Mao Zedong
e) led directly to the takeover of the Manchus in 1644