Niobium Metal Becomes a Superconductor (With Electrical Resistance Equal to Zero)when

Niobium metal becomes a superconductor (with electrical resistance equal to zero) when cooled below 9 K.If superconductivity is destroyed when the surface magnetic field exceeds 0.100 T,determine the maximum current a 3.43-mm-diameter niobium wire can carry and remain superconducting.(µ₀ = 4π × 10−⁷ T⋅m/A)

A) 1720 A
B) 273 A
C) 136 A
D) 860 A
E) ​2690 A