HURRY, I NEED HELP NOW PLEASE!?

Which of the following is a reasonable method to investigate magnetic poles to determine the flow of electrons?

a)Momentarily pass an electrical current through an iron nail. Then hold the nail beside a compass to determine the North and South poles of the temporary magnet you created.

b)Take a long piece of wire and wrap it around an aluminum bar. Connect the two ends of the wire to a battery and let it run for a few moments. Then place the magnet near the aluminum bar.

c)Continuously rub two iron nails against each other for a few moments. Then hold one nail beside a compass todetermine the North and South poles of the temporary magnet you created.

d)Suspend a bar magnet from a string attached to a ring stand. Place a paperclip hanging from the magnet. Without touching the paperclip, slowly insert a piece of aluminum foil between the paperclip and magnet to see if the paperclip falls off.