In part C of the lab, when two wires are in series, so that current flows in opposite directions inside them, we see that the wires move . a. towards each other (they attract)
b. away from each other (they repel)
c. both the wires move downwards towards the floor
d. both the wires move upwards towards the ceiling

The correct option is B.

away from each other (they repel)

Explanation:

This because when current flows in opposite direction in wire, the electrons in them are at high density or electrons in the wires will be at high density which is as a result of contraction of the length due to relativistic of the length, this make the wires to move away from each other or repel.

it is called kinetic energy

there are no contact forces mentioned on the list of choices that you've provided.