The correct answer is option 2: Rajya Sabha. The Rajya Sabha is presided over by a non-member, who is known as the Vice President of India. The Vice President is the ex-officio Chairman of the Rajya Sabha and is responsible for maintaining order and conducting the proceedings of the house. In contrast, the Lok Sabha (option 1) is presided over by the Speaker, who is a member of the Lok Sabha. Similarly, the Vidhan Sabha (option 3) is presided over by the Speaker, who is a member of the state legislative assembly. The Vidhan Parishad (option 4) is presided over by its Chairman, who is elected by the members of the Vidhan Parishad. Therefore, the Rajya Sabha is the only option where a non-member presides over the proceedings.