Explanation
Correct answer: D.
Choice D is the best answer because it accurately describes an aspect of Chavela Vargas that the text indicates is unusual among ranchera artists. According to the text, Vargas differed from other ranchera singers by slowing the tempo of classic songs, which allowed her to express the emotional quality of the lyrics more fully.
Why the other choices are wrong
Choice A
Choice A is incorrect because the text states that Vargas possessed an unusually raspy voice for a ranchera singer, not a clear and polished voice.
Choice B
Choice B is incorrect because the text indicates that Vargas was known to perform songs written from a male point of view, not that she avoided such songs.
Choice C
Choice C is incorrect because nothing in the text suggests that Vargas disliked performing classic songs. Rather, it suggests that she found innovative ways of performing them to emphasize their emotional content, which seems to suggest an affinity for such songs, not dislike.