Answer choice (E) is supported by the first sentence: "the corrido, a type of narrative folk song, comes from a region half in Mexico and half in the U.S. known as the Lower Rio Grande Border." The passage then goes on to describe the features of corridos.
This structure suggests that this is the beginning of a chapter/entry on corridos in a book describing various North American folk song forms.
Answer choice (C) can be eliminated by the same sentence which supports answer choice (E). If the passage was drawn from a newspaper from the Lower Rio Grande Border, it would not need to explain the location of the region as its readership would be from there.
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