Let's graph the following functions.
[tex]\begin{gathered} f(x)=2^x \\ g(x)=(\frac{1}{2})^x \end{gathered}[/tex]
The image below shows the graph.
According to the graph, the difference between the function is that f(x) is increasing and g(x) is decreasing, this behavior is caused by the base of the powers, the base 1/2 (between 0 and 1) gives a decreasing exponential function, and the base 2 (greater than 1) gives an increasing exponential function.
Hence, C is the right answer.
