Answer: To adapt this excerpt for a modern audience, the word that most needs updating is C. doth.
Explanation: The word "doth" is an archaic form of conjugating the verb "do" into the third person singular of the present tense. In that way, "doth" was a verb form used in the past. In order to adapt the excerpt provided for a modern audience, the word "doth" should be replaced with "does", which is the form that we use today to conjugate the verb "do" into the third person singular of the present tense.