a
$\because$ ${\theta _1} < {\theta _2}$ $\Rightarrow$ $\tan {\theta _1} < \tan {\theta _2}$
$\Rightarrow$ ${\left( {\frac{V}{T}} \right)_1} < {\left( {\frac{V}{T}} \right)_2}$
$PV = \mu RT$ from $\,\frac{V}{T} \propto \frac{1}{P}$
So, ${\left( {\frac{1}{P}} \right)_1} < {\left( {\frac{1}{P}} \right)_2}$ $\Rightarrow$ ${P_1} > {P_2}$