How can an iron nail be magnetized permanently​

With only basic materials such as a permanent magnet, electrical wires and a battery, a teacher can demonstrate different ways to magnetize an iron nail. He can turn a nail into an electromagnet, or permanently magnetize it by rubbing it with another magnet.

the answer would most likely be c, because if it's a comical piece of information, it may likely not be true, if it's a site that allows anybody to edit the content, it could mean a five year old is typing the info, and if it's a tv show produced by a celeb, it may have a biased opinion.