From the given alternatives, choose the one which best expresses the sentence in Active/Passive voice.
The teacher was reading out the instructions.

The instructions were being read out by the teacher.

The correct answer is The instructions were being read out by the teacher.

The original sentence is in the continuous active voice, with the subject "teacher" and the verb "was reading". To change it to passive voice, we make the object of the active sentence, "instructions", the subject of the passive sentence. The verb "was reading" becomes "were being read", and we add the preposition "by" to show who is doing the action. This gives us the passive voice sentence "The instructions were being read out by the teacher".

The other options are incorrect.

• The instructions were read by the teacher is in the simple past passive voice. This sentence is not appropriate for the original sentence, which describes an action that was happening in the past.
• The instructions had been read out by the teacher is in the past perfect passive voice. This sentence is not appropriate for the original sentence, which does not describe an action that was completed in the past.
• The instructions had been read by the teacher is in the past perfect active voice. This sentence is not appropriate for the original sentence, which does not describe an action that was completed in the past.