OG详解-OG10 文法 Q15

Choice A is the best answer. Noting that “guerdon” is of Anglo-French origin and “Laodicean” is of ancient Greek origin, the sentence uses “while” to emphasize a difference in the origins of the two words. 
Choice B is incorrect. While the sentence emphasizes two words used in the Scripps National Spelling Bee, it doesn’t emphasize (or mention) the words’ linguistic origins. Choice C is incorrect. While the sentence specifies the linguistic origin of one word used in the Scripps National Spelling Bee, it doesn’t mention the other word or emphasize a difference in the two words’ origins. Choice D is incorrect. While the sentence makes a generalization about words used in the Scripps National Spelling Bee, it doesn’t emphasize a difference in the words’ origins.