Sentence Correction (SC) | Although Xanadu Sentinels fiercely guard the Imperial palace,

Although Xanadu Sentinels fiercely guard the Imperial palace,acting as security sieves and thus protecting the royal properties from either destruction or theft, they also facilitate the opium trade in the rural hinterland.

A. acting as security sieves and thus protecting Royal properties from either destruction or theft, they also facilitate
B. acting as security sieves and thus protecting Royal properties either from destruction or theft, while also facilitating
C. act as security sieves
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