Answer: Option D is correct .
Step-by-step explanation:
Since we have given that
[tex]f(x)=4(3)2x[/tex]
[tex]f(x)=24x[/tex]
In option D,
[tex]f(x)=4(6x)\\\\f(x)=24x[/tex]
Otherwise ,
In all other options , there is no other function whose value comes out to be 24x.
Like , in option b,
[tex]f(x)=4(9)=36x[/tex]
which is not equivalent to
[tex]f(x)=4(3)2x[/tex]
Hence, option D is correct.