The polymer chains are held together by hydrogen bonding in a polymer $X$. Polymer $X$ is formed from monomers $Y$ and $Z$. What are $Y$ and $Z$ ?

$CH_2=CH-C_6H_5$	$H_2N(CH_2)_6NH_2$	$CH_2=CH-CH=CH_2$	$CH_2=CH-CN$	$HO_2C(CH_2)_4CO_2H$
$A$	$B$	$C$	$D$	$E$

• A
  $A, C$
• B
  $B, E$
• C
  $C, D$
• D
  $A, A$