Teflon, polystyrene and neoprene are all

( a) and (b) are correct because their monomers are unsaturated. 

Teflon $C{F}_2=C{F}_2$

Polystyrene$\mathrm{Ph}-\mathrm{CH} = {\mathrm{CH}}_2$

${\mathrm{CH}}_2=\mathrm{C}\left(\mathrm{Cl}\right)-\mathrm{CH}={\mathrm{CH}}_2$

(c) and (d) are ruled out.