As per given by the quetion,
The given exponential function is,
[tex]f(x)=2^x_{^{}}[/tex]
Now,
From the concept of compression.
When we compress the function, y=f(x) by scale factor k, where k>1, then the function after compression will become;
[tex]y=f(kx)[/tex]
So,
From the given function,
[tex]f(x)=2^x[/tex]
And, the scale factor is given that ,
[tex]k=3[/tex]
Then,
From concept of compression,
[tex]\begin{gathered} y=f(kx) \\ y=f(3x) \\ f(3x)=2^{(3x)} \end{gathered}[/tex]
Hence, the option D is correct.
