The correct answer is <span>B. A customer who has fewer than ten items may use the express line.
A is incorrect because it should be "I can barely hear," and not "I can't barely hear;" C is incorrect because it should be "fewer" credits, and not "less" given that credits is a countable noun; D is incorrect because it should be "She scored well on the quiz" given that you should use an adverb rather than an adjective after a verb.
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I believe your answer is The words modest and unimpressive impart a modest tone. Hope this helps!
-Lion
