The diagram shows Ned’s movement as he left his house and traveled to different places throughout the day. A line, which turns at labeled black boxes with a key showing how far 1 mile is on the line. The line starts at V Ned's House and runs right to W Pet Store then down and right to X Library then right to Y Swimming Pool then up and right to Z Gym.
Which reference point should be used to find out how far Ned traveled when he went from the pet store to the swimming pool?

V
W
X
Z