The correct match between Item $I$ and Item $II$ is

Item $I$	Item $II$
$A$. Allosteric effect	$P$. Molecule binding to the active site of enzyme
$B$. Competitive inhibitor	$Q$. Molecule crucial for communication in the body
$C$. Receptor	$R$. Molecule binding to a site other than the active site of enzyme
$D$. Poison	$S$. Molecule binding to the enzyme covalently

• A
  $A \to R, B \to P, C \to Q, D \to S$
• B
  $A \to P, B \to R, C \to Q, D \to S$
• C
  $A \to R, B \to P, C \to S, D \to Q$
• D
  $A \to P, B \to R, C \to S, D \to Q$