Two Wires,A and B,are Parallel to Each Other and Separated

Multiple Choice

Two wires,A and B,are parallel to each other and separated by a distance of 30 cm.Wire A carries a current of 1.2 A in one direction while wire B carries a current of 3.1 A in the opposite direction.Where is the magnetic field equal to zero?

A) between the wires and 8 cm from A
B) between the wires and 10 cm from A
C) exactly halfway between the wires
D) outside the wires and 4 cm from A
E) outside the wires and 19 cm from A