UPSC Prelims 2019 Answer Key Analysis
WEBJun 4, 2019 · UPSC Prelims Answer Key 2019 On this page Drishti IAS, will share the answer key analysis of UPSC Civil Services Preliminary Examination 2019 ... Extraction of rare earth elements (b) Natural gas extraction technologies (c) Hydrogen fuelbased automobiles ... Coal sector was nationalized by the Government of India under Indira .