The following table is regarding $ABO$ blood group. Identify $W, X, Y, Z$.

Genotype	Blood group
$I^{A} I^{A}$	$A$
$W$	$A$
$I^{B} I^{B}$	$B$
$X$	$B$
$I^{A} I^{B}$	$Y$
$Z$	$O$

• A
  $W \rightarrow I^{A} I^0, X \rightarrow I^{B} I^0, Y \rightarrow I^0 I^0, Z \rightarrow AB$
• B
  $W \rightarrow I^{A} I^0, X \rightarrow I^{B} I^0, Y \rightarrow AB, Z \rightarrow I^0 I^0$
• C
  $W \rightarrow I^{B} I^0, X \rightarrow I^{A} I^0, Y \rightarrow AB, Z \rightarrow I^0 I^0$
• D
  $W \rightarrow I^{B} I^{A}, X \rightarrow I^{A} I^{A}, Y \rightarrow AB, Z \rightarrow I^0 I^0$