OE


The key here is that the sentence tells us that his “silver tongue” makes it hard to concentrate on the meaning of his words. To have a silver tongue is to be noted for the pleasantness of one’s speech, so you are looking for a pair of answers that mean “pleasing.” (C) stumbling, (D) laconic, and (F) strident all are unrelated to the pleasantness of his tone, and while (B) concise language may be an attribute of a skilled orator, it will not create a similar sentence to one created by either of the other two possible answers. (A) mellifluous and (E) euphonic both mean “to be sweet or pleasing,” and both are often used in reference to speech.
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