Mandarin, the language was declared the official language of china in 1956, was spoken

c. by Han Chinese

Explanation:

The standard chines also known as the standard mandarin is an official language of the chines people and is pronounced on the basis of the Beijing dialects, Hanyu or language of the Han people was an umbrella term used in the Chinese. When the republic of china was established in 1912 the national language was promoted more by the communist party that declared that all the education must be conducted in Mandarin and bout 70% of the population in china speaks mandarin.

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