Consider the following statements regarding India's vehicular emission and fuel-efficiency regulatory framework:

Statements

1. Bharat Stage emission norms primarily regulate fuel efficiency (kilometres per litre) of vehicles, while CAFE standards govern tailpipe pollutant limits such as nitrogen oxides and particulate matter.
2. The transition from BS VI to BS VII forms part of a wider regulatory architecture that also encompasses CAFE fuel-efficiency standards, E20 fuel compatibility requirements, and onboard diagnostics norms.
3. Selective Catalytic Reduction (SCR) systems, particulate filters, and urea-dosing are among the exhaust-treatment technologies typically required to meet tighter nitrogen-oxide emission limits for diesel vehicles.