Answer:
A. alternating current
Explanation:
An alternating current is that which changes polarity in a periodic manner. It is generated when a conductor cuts or breaks magnetic field lines in such a way that it periodically alternates or switches its direction of motion or position between the north and south poles of the magnetic field.
The switching of the direction of motion makes the polarity of the induced current to change in a manner that corresponds to the motion of the conductor. This is what generates an alternation current (a.c)
