A 12.0 of gas sample of gas occupies $19.2\;L$ at STP. what is the molecule weight of this gas ?

Question

$\begin{array}{1 1} (a)\; 14.0g/mol \\(b)\; 12.5g/mol \\ (c)\;13.8g/mol \\ (d )\;17.4g/mol \end{array}$