Which of the following angle pairs best describes angles 6 and 4 in the graphic below?

Choice C) Same-side interior angles



Angle 4 and angle 6 are on the same side, in this case the right hand side of the transversal line (line t). In addition, they are on the interior of the "train tracks" horizontal  lines (line a and line b). Combine this and this is why the two angles are same-side interior angles

Side note: if line a is parallel to line b, then angle 4 and angle 6 add to 180 degrees. At this point, they are considered supplementary.

The answer to your question is 1/9