Parallel Plates: Two Very Large Parallel Sheets a Distance D

Multiple Choice

Parallel plates: Two very large parallel sheets a distance d apart have their centers directly opposite each other. The sheets carry equal but opposite uniform surface charge densities. A point charge that is placed near the middle of the sheets a distance d/2 from each of them feels an electrical force F due to the sheets. If this charge is now moved closer to one of the sheets so that it is a distance d/4 from that sheet, what force will feel?

A) 4F
B) 2F
C) F
D) F/2
E) F/4