The correct answer is (a). Article 224A of the Constitution of India provides for the appointment of retired High Court Judges at the sittings of High Courts.
Article 224A states that the Chief Justice of a High Court may, with the consent of the President, request any retired Judge of that Court or of any other High Court to sit and act as a Judge of that Court, and any such Judge may, while so sitting and acting, receive such remuneration as the President may fix.
This provision was inserted in the Constitution by the Constitution (Forty-second Amendment) Act, 1976. The purpose of this amendment was to enable the Chief Justice of a High Court to appoint retired High Court Judges to sit and act as Judges of that Court, in order to meet the shortage of Judges in High Courts.
Article 224A has been used on a number of occasions to appoint retired High Court Judges to sit and act as Judges of High Courts. For example, in 2017, the Chief Justice of the Madras High Court appointed a retired Judge of that Court to sit and act as a Judge of the High Court, in order to meet the shortage of Judges in that Court.
Article 224A is a useful provision that enables the Chief Justice of a High Court to appoint retired High Court Judges to sit and act as Judges of that Court, in order to meet the shortage of Judges in High Courts.