How can the graphs of $f(x)=\frac{5}{4}(x-28)$ and $g(x)=\frac{4}{5} x+28$ be used to prove that $f(x)$ and $g(x)$ are inverse functions?

AShow that the graph of $g(x)$ is a translation of the graph of $f(x)$.

BShow that the graph of $g(x)$ is a rotation about the origin of the graph of $f(x)$.

CShow that the graph of $g(x)$ is a reflection about the $x$-axis of the graph of $f(x)$.

DShow that the graph of $g(x)$ is a reflection about the line $y=x$ of the graph of $f(x)$.