Which of the following metals is primarily used in structures due to its high strength-to-weight ratio?

Aluminum is primarily used in structures due to its high strength-to-weight ratio because it is both lightweight and strong. This characteristic makes aluminum an ideal material for a variety of applications, particularly in the construction of structures and components where minimizing weight while maintaining strength is essential. For instance, in the aerospace and automotive industries, aluminum is extensively used because it helps improve fuel efficiency and performance without compromising structural integrity.

Additionally, aluminum has good corrosion resistance, which contributes to its durability in various environments. This combination of properties has led to its widespread use in applications ranging from building frameworks to airplane parts and even in the manufacturing of sports equipment. These characteristics set aluminum apart from metals like iron, bronze, and copper, which may not offer the same balance of strength and lightweight benefits that aluminum does.