Answer : 2. "HCFC 141B"
Explanation :

According to a report by the Environment Ministry and UNDP, India has successfully phased out the ozone depleting and climate warming chemical HCFC 141b (1,1-dichloro-1-fluoroethane) and is introducing another such gas in new equipment manufacturing. Is ahead of schedule in finishing. Against the 35 per cent phase-out target for HCFCs, India has achieved an impressive reduction of 44 per cent.