0.0000002457 (option D)
Explanations:The given scientific notation is:
[tex]2.457\text{ }\times10^{-7}[/tex][tex]10^{-7}\text{can be interpreted in decimal as 0.0000001}[/tex]Then multiply 0.0000001 by 2.457
[tex]\begin{gathered} 2.457\text{ }\times10^{-7}=\text{ 2.457 }\times0.0000001 \\ 2.457\text{ }\times10^{-7}=\text{ }0.0000002457 \end{gathered}[/tex]