In a pseudo first order hydrolysis of ester in water,the following results were obtained.

$t/s$	$0$	$30$	$60$	$90$
$Ester/mol\, L^{-1}$	$0.55$	$0.31$	$0.17$	$0.085$

What will be the average rate of reaction between the time interval $30$ to $60$ seconds?

• A
  $1.91 \times 10^{-4} \, M \, s^{-1}$
• B
  $4.67 \times 10^{-3} \, mol \, L^{-1} \, s^{-1}$
• C
  $1.98 \times 10^{-3} \, s^{-1}$
• D
  $2.07 \times 10^{-2} \, s^{-1}$