bare wire, plastic rod, battery bare wire, iron rod, light bulb insulated wire, iron rod, battery insulated wire, plastic rod, light bulb
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which of the following groups of materials would most likely be used to build an electromagnet?
Possibilities:
- bare wire, plastic rod, battery
- bare wire, iron rod, light bulb
- insulated wire, iron rod, battery
- insulated wire, plastic rod, light bulb

insulated wire, iron rod, battery