When something says 'solve for the system of equations' they are looking for a point where the graph of the two functions intersects. Since they give you the graph, the two functions approximately intersect somewhere between the x-value of -6 and -7 (i.e. -6.5) and somewhere between the y-value of -3 and -4 (i.e. -3.5). So, the closest estimate is (-6.5, -3.5) or A.
