China built artificial islands in the South China Sea primarily to exert military influence by establishing military bases and enhancing naval power in the region. While trade and technology are considerations, the primary purpose is military in nature. This strategy allows China to control contested territories and important maritime routes. ;
The artificial islands in the South China Sea were primarily built by China to exert military influence, enhancing their naval capabilities in a strategically important region. These constructions allow China to establish military bases and control contested territories. Therefore, the correct answer is C: exert military influence.
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