GS Paper 3 — Economy, Agriculture, Science & Technology, Environment, Disaster Mgmt, Internal Security.
The applied paper. Six disciplines that share a method — read the data, name the trade-offs, and write the answer in the language of policy, not opinion.
Economy
Growth, fiscal and monetary policy, banking, external sector, and inclusive development.
Agriculture
Productivity, land reforms, irrigation, MSP, and the rural-economy interventions.
Science Technology
Space, defence, IT, biotech, nano, and the policy questions each raises.
Environment
Biodiversity, climate change, pollution, India's statutes, and global negotiations.
Disaster Management
The DM framework, hazard-specific protocols, and the institutional architecture.
Internal Security
Terrorism, insurgency, cyber, money-laundering, and the agencies that handle them.
The other papers
UPSC Mains GSGS Paper 1
History, Art & Culture, World History, Geography, Indian Society
GS Paper 2
Polity, Governance, Social Justice, International Relations
GS Paper 3
Economy, Agriculture, Science & Technology, Environment, Disaster Mgmt, Internal Security
GS Paper 4
Ethics, Attitude, Emotional Intelligence, Probity, Case Studies