The correct answer here is the last option
Mahan argues clearly that a strong navy is required in order for United States to expand far beyond its shores and its territory in order to become a super power. Manifest Destiny is a belief that first referred to the destiny of the settlers to spread across North America and later beyond. Here Mahan says that in order to do that the government needs to provide supply points for its navy.
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It stands for United Kingdom
<span>Arab traders took over the Silk Road trade, which undermined the Tang economy.</span>