Dear Sir / Ma'm, as for now, keep it blank. On reaching the examination centre, you can ask the authorities or they themselves will tell you what to fill in there during the document verification process. If nothing is told to you there, you might as well ask the invigilators during the examination as to what has to be filled in there. Do not forget to preserve a zerox copy of the admit card as the authorities will be taking your admit card during the examination, and the procurement of the admit card is important during the counselling process.