The detail from the excerpt that best creates an anxious tone is C. Sadako nods her head with "unnecessary vigor."
This is because the actions of Sadako show that she is anxious and this is shown in the tone as she nods her head with "unnecessary vigor."
This refers to the author's attitude to a text that affects the general atmosphere of the text.
Hence, we can see that the detail from the excerpt that best creates an anxious tone is C. Sadako nods her head with "unnecessary vigor."
This is because the actions of Sadako show that she is anxious and this is shown in the tone as she nods her head with "unnecessary vigor."
Read more about tones here:
https://brainly.com/question/819739
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