What was an accomplishment by the song dynasty of china?
a. the song rulers expanded the use of coinage and paper currency.
b. the song rulers defeated kublai khan after a long war.
c. the song rulers expanded into the mongol empire.
d. the song rulers first evaluated officials using civil service tests.

The accomplishment by the Song dynasty of China is that the song rulers expanded the use of coinage and paper currency.

Explanation

The period of Song dynasty was the golden period of China with several advances in technology, art and administration. Earliest  form of paper money in the world developed during the period of Song rulers and it was called Jao Zi. It was one of the popular paper currency of that time.

The high development of commerce is indicated by this factor. The Song period was also famous for the technological advances. The world famous inventions, compass,gun powder and movable printer was in China during the Song period.

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