Rachel drew the two graphs below.

Graph R
Graph S

Rachel says that Graph R has a greater constant of variation than Graph S. Which statement explains whether Rachel is correct?
A. Rachel is correct; Graph S is nonproportional.
B. Rachel is correct; Graph R goes farther along the x-axis.
C. Rachel is not correct; both graphs go through the origin and have the same constant of variation.
D. Rachel is not correct; Graph S is steeper than Graph R.