JEE Main 24 Feb 2021 Shift 2 Solved Paper

Buna-S is the co-polymer of but 1,3 -diene and styrene as follows.Styrene butadiene rubber is also called buna- S, in which ' Bu ' stands for butadiene, 'na' stands for sodium and ' S ' stands for styrene.
Since, butadiene and styrene is one of the constituent monomer of given polymer.