Two long wires carrying currents I _{1 }and I_{2} in the directions shown, with I _{2} = 4I_{1}, cross at right angles in the xy plane. Consider the points A = (2d, d) and B = (2d, −d), where d is a positive number. Find the ratio of the magnitudes of the magnetic fields at these two points, i.e., what is |B_{B}/B_{A}|?

A) 9/7

B) 1

C) 5/3

D) 4

E) None of these