This question tests your understanding of converting an active voice sentence into its passive voice equivalent, specifically for the past perfect tense. The original sentence, "She had cooked dinner," is in the active voice, past perfect tense (Subject + had + past participle + Object).
To transform a past perfect active sentence into passive voice, the structure changes to: Object + had + been + past participle + (by Subject). In this case, "dinner" is the object, so it becomes the subject of the passive sentence. Following the rule, "dinner" is followed by "had been" and the past participle "cooked."
- A: "Dinner is cooked" is incorrect because it uses the simple present passive tense.
- B: "Dinner was cooked" is incorrect as it uses the simple past passive tense.
- D: "Dinner has been cooked" is incorrect because it uses the present perfect passive tense.
Only C: "Dinner had been cooked" correctly applies the past perfect passive voice structure, maintaining the original tense and meaning while shifting the focus from the doer of the action to the action itself and its recipient.