A function f defined on the set R of real numbers
\begin{itemize}
\item For every $x \in [ -10,10 ]$, $f ( x ) = | x |$
\item For every $x \in R$, $f ( x ) = f ( x + 20 )$
\end{itemize}
satisfies these properties. Accordingly, what is the value of $f ( 117 )$?\\
A) 3\\
B) 4\\
C) 6\\
D) 7\\
E) 9