Match the dimensionless numbers in $Group–I$ with the ratios in $Group–2$.
$\begin{array}{cc}\\
&\text{Group-1} & \text{Group-2} \\
&\text{P. Biot number} & \text{ I. $\frac{buoyancy force}{viscous force}$} \\
&\text{ Q. Schmidt number} & \text{II. $\frac{internal thermal resistance of a solid}{boundary layer thermal resistance}$} \\
&\text{R. Grashof number} & \text{III. $\frac{momentum diffusivity}{mass diffusivity}$} \\ \\ \end{array}$
- $P-II$, $Q-I$, $R-III$
- $P-I$, $Q-III$, $R-II$
- $P-III$, $Q-I$, $R-II$
- $P-II$, $Q-III$, $R-I$