Look at the pictures.
On the first picture we have a graph of function [tex]y=3^x[/tex]
If y = f(x), then y = f(−x) is its reflection about the y-axis (the second picture).
[tex]f(x)=3^x\to f(-x)=3^{-x}[/tex]
If y = f(x), then y = -f(x) is its reflection about the x-axis (the 3th picture).
[tex]f(x)=3^x\to -f(x)=-3^x[/tex]
If [tex]f(x)=3^x\to-f(-x)=-3^{-x}[/tex] is its reflection about the x-axist
and y-axist (4th picture).
Answer: Graph D.