Which monomer could be used to form a polymer with the following repeating unit?

A.     \({\text{C}}{{\text{H}}_{\text{3}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{Cl}}\)

B.     \({\text{C}}{{\text{H}}_{\text{2}}}{\text{ClC}}{{\text{H}}_{\text{2}}}{\text{Cl}}\)

C.     \({\text{C}}{{\text{H}}_{\text{2}}}{\text{CHCl}}\)

D.     CHClCHCl

C