Which of the following is a valid ladder type among the four listed?

• A. Step ladder
• B. Rope ladder
• C. Straight ladder
• D. Platform ladder

Answer: (C)

Ladders come in different designs, but this item is testing the basic, lean-to ladder form. A straight ladder is the classic rigid ladder you lean against a sturdy surface and secure at the top and bottom. It represents the standard ladder design that you can set at the proper angle (about 75 degrees) and climb with three points of contact, making it a valid general-purpose ladder type. A rope ladder isn’t a rigid ladder; it relies on rope and lacks the side rails and rigid rungs that provide stable footing, so it isn’t treated as a standard ladder for typical work. The other two—step ladders and platform ladders—are self-supporting or provide a built-in platform and thus belong to a different ladder category, not the straightforward lean-to type emphasized here. So the straight ladder fits the conventional ladder form and is the best choice in this context.