Suppose at
$T = 27^{\large\circ}C = 300K$
$T_1 = 37^{\large\circ}C = 310K$
V = 1 litre
$V_1 = ?$
At constant pressure = $\large\frac{V}{T} = \large\frac{V_1}{T_1}$
$\Rightarrow \large\frac{1}{300} = \large\frac{V_1}{310}$
$\Rightarrow V_1 = \large\frac{310}{300}$
$\Rightarrow 1.0333 \; litre$
Since capacity of flask is 1 litre
Volume of air escaped out = 1.0333 - 1
$\Rightarrow$ 0.033 litre
$\Rightarrow$ 33.3 mL
Hence answer is (C)