Answer: Line BD is the line of intersection.
1) C is just a point and therefore cannot be a line by itself.
2) Line AC includes points in plane N, but not in plane J. In order to be a line of intersection, all points within the line must be found in both planes.
3) BC is a segment, not a line. A geometric postulate relating the intersection of two planes states that their intersection is exactly one line. A segment does not continue infinitely like a line does.
