Four Point Charges Are Located at the Corners of a Square

Four point charges are located at the corners of a square, $1.00 \mathrm{~m}$ by $1.00 \mathrm{~m}$ . On each of two diagonally opposite corners are $1.00 \mu \mathrm{C}$ charges. On each of the other two corners are $-1.00 \mu \mathrm{C}$ charges. What is the direction of the force on each charge?

A) positive and negative charges both away from the center of the square
B) no direction (net force on each charge $=0$ )
C) positive charges away from away from the center of the square, negative inward toward the center
D) positive and negative charges both toward the center of the square
E) negative charges away from away from the center of the square, positive inward toward the center