Which of the following statements regarding the 'advisory jurisdiction of Supreme Court' is correct:
1. The opinion of Supreme Court may be sought by the President on any question of law or fact
2. In case the opinion of the Supreme Court is sought it is bound to give
3. The advice given by Supreme Court on matters referred to it is binding on the President
4. Advisory jurisdiction of Supreme Court can also be exercised over disputes arising out of references made over preconstitutional treaties