$40\; gms$ of $NaOH$ contains

Question

$\begin{array}{1 1} (a)\; 6.022 \times 10^{23}\; molecules \\ (b)\; 1\; molecule \\ (c)\; 13.24 \times 10^{21}\; molecules \\ (d)\; 6.022 \times 10^{21}\; molecules \end{array}$