What is a key characteristic of metals such as copper and iron?

Copper and iron are characterized by their high electric and thermal conductivity, which is a fundamental property of most metals. This means they are able to efficiently conduct electricity and transfer heat, making them desirable materials for various applications including electrical wiring, soldering, and heat exchangers.

Copper, in particular, is highly recognized for its exceptional conductivity, which is why it's commonly used in electrical applications. Iron, while not as conductive as copper, still possesses a significant ability to conduct electricity and heat, making both metals valuable in industrial contexts where conductivity is essential. These characteristics also contribute to their widespread use in construction, electronics, and manufacturing.

Other options represent attributes that do not accurately reflect the typical properties of copper and iron. High corrosion resistance is not a strong trait of iron, as it tends to rust in wet environments, while copper does have some resistance to corrosion but not as high as other metals like stainless steel. Low density and strength do not apply to these metals; in fact, they are known for their strength, especially in structural applications. Lastly, both metals have relatively high melting points compared to materials categorized with low melting points, which are typically non-metals or alloys.