The correct answer is: B. eddy current loss will increase.
Eddy current loss is a type of energy loss that occurs in a conductor when an alternating current is passed through it. The eddy currents are induced in the conductor by the changing magnetic field of the alternating current. The eddy currents flow in closed loops and cause heat to be generated in the conductor. The amount of eddy current loss is proportional to the square of the frequency of the alternating current. This is because the eddy currents are induced by the changing magnetic field of the alternating current, and the rate of change of the magnetic field is proportional to the frequency of the alternating current.
Therefore, for a given applied voltage, with the increase in frequency of the applied voltage, the eddy current loss will increase.
Option A is incorrect because eddy current loss increases with the increase in frequency of the applied voltage.
Option C is incorrect because eddy current loss does not remain unchanged with the increase in frequency of the applied voltage.
Option D is incorrect because eddy current loss is a type of energy loss that occurs in a conductor when an alternating current is passed through it.