Choose the appropriate Passive Sentence from the following for:

The rain had drenched the pavement completely before the bus arrived.

The pavement had been drenched completely by the rain before the bus arrived.

The correct answer is Option (4) → The pavement had been drenched completely by the rain before the bus arrived.
Explanation:
1. Passive Voice: The passive voice shifts the focus from the subject (the rain) to the object (the pavement). In this case, we're emphasizing the action done to the pavement rather than the rain itself.
 
2. Past Perfect Tense: "Had been drenched" is in the past perfect tense, indicating that the action of drenching the pavement (by the rain) was completed before another past event (the arrival of the bus).
3. Adverbial Phrase Placement: "Before the bus arrived" effectively emphasizes the sequence of events, showing that the drenching of the pavement occurred prior to the bus's arrival.

This construction effectively conveys the chronological order of events and emphasizes the state of the pavement resulting from the rain.