NPS (National Pension System) is applicable to all new employees of Central Government service (except Armed Forces) and Central Autonomous Bodies joining Government service on or after 1st January 2004. It is applicable to all the employees of State Governments, State Autonomous Bodies joining services after the date of notification by the respective State Governments. All citizens of India between the age of 18 and 60 years can join NPS. Recently, NRIs were also allowed to open NPS accounts online. Option (d) is wrong as Armed Forces are excluded from the Central Government NPS.