How was the expansion of trade and exploration in the postclassical era important to china during the song dynasty?

a. the confucian civil service exam was replaced by exams used in west africa.

b. china adopted the systems of feudalism and communism that were used in medieval europe.

c. china was able to expand its markets along the silk road and increase maritime trade.

d. christianity and islam spread to china and replaced daoism and buddhism as official religions.

A. The Confucian civil service exam was replaced by exams used in West Africa.

Explanation:

During the Song (Sung) Dynasty (960-1276), innovation was profoundly cutting-edge in fields as differing as farming, iron-working, and printing. To be sure, researchers today discuss a Song financial transformation.  

The populace developed quickly amid this time, and an ever increasing number of individuals lived in urban areas.  

The Song system of government was also advanced for its time. The upper-dimensions of the administration were staffed by very instructed scholar-officials selected through competitive written examinations.

the qing dynasty placed strict limits on foreign merchants' ability to trade in china.

there has only been 12 presidents. the 12th president is/was moon jae-in