#1**+2 **

In three-dimensional geometry, skew lines are two lines that do not intersect and are not parallel. A simple example of a pair of skew lines is the pair of lines through opposite edges of a regular tetrahedron.

( I had to look up that definition)

SO by definition

GC is the only one that fits....the others are parallel or intersect.

ElectricPavlov Mar 4, 2018