Choose the correct passive voice transformation of the sentence: What had they done to ensure the project's success before the official launch?
Show answer & explanation
Correct answer: B
Explanation
The original sentence is "What had they done to ensure the project's success before the official launch?". This sentence is in the Past Perfect tense ("had done").
To convert a Past Perfect active sentence into passive voice, the structure for interrogative sentence is: Wh-word + had + object + been + past participle + by agent?
Option ‘B’ follows these changes.