Answer:
C. China.
Step-by-step explanation:
The construction began officially in 1863 planned by Theodore Judah and authorized one year earlier by the Congress. But it was not until 1865 that the construction began more efficiently. The head of the workforce, James Harvey Storbridge, hired Cantonese workers. By 1868 the Chinese workforce grew up to 12,000 laborers that constituted 80% of the entire workers.
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