Read the sentence. someone sang a solo during the holiday concert. the best reason to revise this sentence using the passive voice is that

The best reason to revise this sentence using the passive voice is that the person uttering the sentence is not sure about who sang the solo.

Explanation:

The sentence above does not have a specific subject, the speaker has chosen to use the indefinte pronoun someone. Indefinite pronouns do not refer to any person, amoun, or thing in particular. As the singer is not mentioned at all, it would be better to put emphasis on the solo itself. This can be done by means of a passive construction. The sentence would be as follows: A solo was sang during the holiday.

The answer to the given question above would be the first option. The best reason to revise this sentence using the passive voice is that the name of the singer is unknown. This entails that the speaker does not consider the name of the singer to be relevant information, or else, the fact that a solo was sang is more important than the singer's name.  

When using the passive voice, the object of the active sentence becomes the subject; therefore, the action is highlighted instead of the doer of the action.

ummcan you clarify what we have to answer? if you do that I will edit answer and add appropriate one to it

(A) The Name of The singer is Unknown

Explanation:

LOOK AT BOLD

Someone sang a solo during the holiday concert.

Someone sang a solo during the holiday concert.

The best reason to revise this sentence using the passive voice is that

the name of the singer is unknown.

the kind of song being performed is unknown.

the length of the concert is unknown.

the type of holiday being celebrated.

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