JEE Main 25 Feb 2021 Shift 1 Solved Paper

Only statement (d) is correct whereas other statements are incorrect. The correct statements are as follows
Buna- N is a synthetic polymer.
Buna- S is an elastomer. Buna- S is polymerised by addition polymerisation method, which needs radical initiator for chain propagation step. Nascent oxygen can be used as an radical initiator.Neoprene is a synthetic rubber not an addition copolymer.