Answer:
X is iron
Explanation:
A conductor is a substance that allows electricity to readily pass through it. The properties of substance determines if it is a conductor or not. Most metals for example are conductors due to the presence of free mobile electrons in their structures. Since the second column is for conductors and our choice is between iron, foam, wood and glass, iron is simply the correct option. Foam, wood and glass are all insulators which do not allow for electrical conduction.
