The correct option is B Gauss
Answer is B.
The gauss, abbreviated as G or Gs, is the cgs unit of measurement of a magnetic field B, which is also known as the "magnetic flux density" or the "magnetic induction". It is named after German mathematician and physicist Carl Friedrich Gauss. One gauss is defined as one maxwell per square centimeter. The cgs system has been formally superseded by the SI system, which uses the tesla (T) as the unit for B. One gauss equals 1×10−4tesla(100μT)(1T=10,000G).