Answer:
Option C:
g(x) = -3^x
Explanation:
Here we can see the graphs of f(x) and the graph of g(x).
By only looking at that, we can see that g(x) is a reflection across the x-axis of f(x).
Remember that for a general function f(x), the reflection across the x-axis is written as:
g(x) = -f(x).
Then, if f(x) = 3^x
and g(x) = -f(x)
replacing f(x) we get:
g(x) = -(3^x) = -3^x
The correct option is C.