Chloroprene is used in making

Which of the following is a biodegradable polymer of the polyamide class?

Which one of the following structures represents the neoprene rubber?

Buna-$S$ is obtained from

Choose the correct option$(s)$ from the following:
$(1)$ Natural rubber is polyisoprene containing trans alkene units.
$(2)$ Nylon-$6$ has amide linkages.
$(3)$ Cellulose has only $\alpha-D$-glucose units that are joined by glycosidic linkages.
$(4)$ Teflon is prepared by heating tetrafluoroethene in the presence of a persulphate catalyst at high pressure.

Bakelite is a cross-linked polymer of formaldehyde and :