25\% \, of ( 50\% \, of 30\% \, of 150 )40\% \, of 2250 is equal to:

Answer: Option A

$$\begin{array}{rl}& \frac{25\%\text{of}\left(50\%\text{of }30\%\text{of }150\right)}{40\%\text{of }2250}\\ & =\frac{25\%\times \left(50\%\times 30\%\times 150\right)}{40\%\times 2250}\\ & =\frac{25}{40}\%\\ & =0.625\%\end{array}$$