UPSC

Hello Atul,
The Union Public Service Commission is India's central agency authorised to conduct the Civil Services Examination, Engineering Services Examination, Combined Medical Services Examination, Combined Defence Services Examination, National Defence Academy Examination, Naval Academy Examination, Special Class Railway Apprentice, Indian Forest Service examination, Indian Economic Service examination, Indian Statistical Service examination, Combined Geoscientist and Geologist Examination, and Central Armed Police Forces (Assistant Commandant) examination.
The agency's charter is granted by the Constitution of India. Articles 315 to 323 of Part XIV of the constitution, titled as Services Under the Union and the States, provide for a Public Service Commission for the Union and for each state. The examination conducted for Civil Servents has a success rate of 0.1percent0.3%.

Hi,
Public Administration is a better choice since that subject is easy to complete and highly scoring. Moreover, the public administration will also be taught once you clear the examination. It's one of the important subjects taught at LBSNNA (Lal Bahadur Shastri National Academy of Administration), Mussoorie. Further, a lot of study material is already available on the net as well as in the market for the preparation of this subject. On the other hand, management is a great subject, but not many UPSC aspirants opt for it. The reason being the length of the subject and not many teachers are available for helping aspirants while preparing this subject. But at the end of the day, its your choice.