Explanation:

- Reverted: This means to return to a previous state or condition. It doesn't fit the context of a voice in empty rooms.

- Resounded: To fill a place with sound or echo loudly. This is suitable for describing Harish's voice in empty rooms as sound tends to echo in such spaces.

- Correct Answer.

- Relapsed: Means to fall back into a previous state, often used in the medical context or behavior. Not suitable for the sound context.

- Resorted: Means to turn to a course of action or strategy. It does not apply to a voice in rooms.