What material is commonly used for escalator step surfaces?

The correct choice is a resilient or slip-resistant material, which is typically used for escalator step surfaces to ensure safety and minimize the risk of slips and falls. This type of material is designed to provide traction underfoot, which is especially important in a moving environment like an escalator.

Using slip-resistant materials enhances the safety of passengers, as they can grip the footstep even when it is wet or has debris on it. This is vital in public places where escalators are frequently used, as it helps ensure the safety of a diverse group of people, including those who may be elderly or unsteady on their feet.

Other materials listed, such as wood and glass, are not practical options for escalator surfaces due to safety and durability concerns. Wood can be prone to wear and tear and does not provide the necessary slip resistance. Glass, while aesthetically pleasing, would pose a significant safety hazard, as it could be slippery and potentially break under stress. Metal, while durable and commonly used in construction, does not inherently provide the necessary slip resistance required for escalator steps.