Select the option that expresses the given sentence in passive voice.

Close all the windows.

Let all the windows be closed.

The correct passive voice of the sentence Close all the windows is Let all the windows be closed.

The active voice of the sentence is Close all the windows. This sentence is in the imperative mood, which is used to give commands or make requests. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "all the windows" and the main verb is "close." The past participle of "close" is "closed." So, the passive form of the sentence is Let all the windows be closed.

The other options are incorrect because:

• Will you close all the windows? is in the interrogative mood, which is used to ask questions.
• Can you close all the windows? is also in the interrogative mood.
• All the windows be closed. is not a complete sentence. It is missing a subject.