The repeat unit of neoprene is $-[\mathrm{CH}{}_2-\mathrm{C}(\mathrm{Cl})=\mathrm{CH}-\mathrm{CH}{}_2]{}^{-}$ ($\mathrm{C}{}_4\mathrm{H}{}_5\mathrm{Cl}$; C 12, H 1, Cl 35.5). A neoprene sample has molar mass $44250\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$. Its degree of polymerisation (neglecting end groups) is

1. A1000
2. B250
3. C500
4. D442