The option that best describes the “thumb-nail” imagery is "It emphasizes Thoreau’s belief that people should carefully choose their commitments," option C.
Imagery is a literary device that appeals to the five senses (sight, taste, touch, smell and hearing) through language. The purpose is to involve the reader and help visualize what is being described. Here, we are analyzing the imagery conveyed by Thoreau as he says "thumb-nail".
Of course, we must take the whole context into consideration to answer this question. In the passage, Thoreau defends that idea that we should lead a simple life, as uncomplicated as possible. Therefore, he says that our commitments should be "half a dozen", kept on our "thumb-nail." In other words, he means we should not have many commitments - our thumb-nail is quite small.
With the information above in mind, we can select option C as the correct answer for this question.
Learn more about imagery here:
https://brainly.com/question/851653
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