context: In addition to the General Assembly Hall, the Parliament also used buildings rented from the City of Edinburgh Council. The former administrative building of Lothian Regional Council on George IV Bridge was used for the MSP's offices. Following the move to Holyrood in 2004 this building was demolished. The former Midlothian County Buildings facing Parliament Square, High Street and George IV Bridge in Edinburgh (originally built as the headquarters of the pre-1975 Midlothian County Council) housed the Parliament's visitors' centre and shop, whilst the main hall was used as the Parliament's principal committee room.
question: Which hall was used as Parliament's principle committee room?
answers.text: main main the main hall