Liquid phase isomerization of $o$-xylene to $p$-xylene using a zeolite catalyst was carried out in a $CSTR$ three sets of kinetic data at different temperatures and stirring speeds were obtained as shown below.

$\begin{array}{|cl|cI|cI|}\hline &\text{} & \text{} & \text{} \\ \hline &\text{temperature ($K$)} & \text{500} & \text{500} & \text{500} & \text{600} & \text{600} & \text{600} & \text{700} & \text{700} & \text{700} \\ \hline &\text{stirring speed ($rpm$)} & \text{1000} & \text{2000} & \text{3000} & \text{1000} & \text{2000} & \text{3000} & \text{1000} & \text{2000} & \text{3000} \\ \hline &\text{reaction rate (mol L$^{-1}$s$^{-1}$)} & \text{0.020} & \text{0.025} & \text{0.025} & \text{0.037} & \text{0.047} & \text{0.047} & \text{0.069} & \text{0.078} & \text{0.086} \\ \hline \end{array}$

The operating condition at which the reaction rate is not controlled by external mass transfer resistance is

1. $T=500\:K$; rpm=$3000$
2. $T=600\:K$; rpm=$1000$
3. $T=700\:K$; rpm=$1000$
4. $T=700\:K$; rpm=$2000$