What materials can portable ladders be made from?

Portable ladders can be made from wood, metal, and fiberglass, which is why this choice is the correct answer.

Wood ladders, traditionally used for many years, offer good stability and are often treated to resist decay. However, they can be heavier and less durable compared to some other materials. Metal ladders, commonly made from aluminum or steel, provide strength and are lightweight, making them easy to transport. Fiberglass ladders are particularly useful because they are non-conductive, making them safe for electrical work.

These materials each serve specific purposes and advantageously cater to various environments and needs, making them appropriate for a range of ladder applications. The other options, while they mention some materials used in ladder manufacturing, do not encompass the full spectrum of commonly used materials, thus making them less comprehensive than the correct choice.