Answer:
C
Step-by-step explanation:
A does not make sense, because since electrons move towards positive change and are repelled by negative charge, they would move towards the smaller negative charge rather than the large one. This also rules out option D.
Option B could potentially be the answer, since during any kind of conduction the end goal is equilibrium, but if B is true than C must also be, and All of the Above is ruled out.
Option C makes the most sense because electrons seek out places where electron density is lower, so they can metaphorically "have more space for themselves"
Hope this helps!