Final answer:
The word that best describes the tone of a letter is respectful.
Step-by-step explanation:
The word that best describes the tone of a letter is Respectful. When writing a letter, it is important to use language that shows respect towards the recipient. A respectful tone helps to establish a positive and professional relationship between the writer and the reader. For example, using polite language, addressing the recipient by their appropriate title, and expressing gratitude are some ways to convey a respectful tone in a letter.
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