Which change would reverse the direction of the electric current generated through electromagnetic induction? moving the magnet slower using more loops of wire in the solenoid using the opposite pole of the magnet using a weaker magnet

Using the opposite pole of the magnet.
Electromagnetic induction is when an emf is induced because there is a change in the magnetic field across the coil.
To have a change in magnetic field, it means that the poles used must be opposite.

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