I would say B. g(x) eventually exceeds f(x) because g(x) is increasing exponentially.
As shown, f(x) = x + 4 and g(x) = (5/4)^x. This shows that f(x) is in fact Arithmetic (since its addition) and g(x) is Geometric (since its multiplication).
On a graph, Arithmetic sequences have a linear shape, while Geometric sequences have a exponential shape.
Example: x = 20
f(x): (20) + 4 = 24
g(x): (5/4)^(20) = 86.7
So, g(x) does in fact eventually exceed f(x).