Explanation:

• Ad hoc Judge: When there is a lack of quorum of the permanent judges to hold or continue any session of the Supreme Court, the Chief Justice of India can appoint a judge of a High Court as an ad hoc judge of the Supreme Court for a temporary period. He can do so only after consultation with the chief justice of the High Court concerned and with the previous consent of the president. The judge so appointed should be qualified for appointment as a judge of the Supreme Court. It is the duty of the judge so appointed to attend the sittings of the Supreme Court, in priority to other duties of his office. While so attending, he enjoys all the jurisdiction, powers and privileges (and discharges the duties) of a judge of the Supreme Court.

• Retired Judge: At any time, the chief justice of India can request a retired judge of the Supreme Court or a retired judge of a high court (who is duly qualified for appointment as a judge of the Supreme Court) to act as a judge of the Supreme Court for a temporary period. He can do so only with the previous consent of the president and also of the person to be so appointed. Such a judge is entitled to such allowances as the president may determine. He will also enjoy all the jurisdiction, powers and privileges of a judge of Supreme Court. But he will not otherwise be deemed to be a judge of the Supreme Court.

Hence only statement 2nd is correct.