AMC 10A 2018 Problem 12

How many ordered pairs of real numbers (x, y) satisfy the following system of equations?

\begin{array}{r} x+3 y=3 \end{array}
\begin{array}{r} || x|-| y||=1 \end{array}

Answer Choices
A. 1
B. 2
C. 3
D. 4
E. 8