Which type of anchor is most appropriate for use in hollow materials?

The hollow wall anchor is specifically designed for use in hollow materials, such as drywall or hollow block. This type of anchor features a mechanism that expands or grips the inside of the wall as the screw is tightened, providing a strong hold in materials that lack solid backing. When properly installed, hollow wall anchors distribute weight effectively and minimize the risk of pulling out, which is crucial when securing items to structures that can be less stable than solid surfaces.

In contrast, the other options serve different purposes and are not suited for installations in hollow materials. Sleeve anchors are best used in solid materials, such as concrete, and provide a strong load-bearing capacity by expanding within the drilled hole. Wedge anchors are also intended for use in solid materials and require a pre-drilled hole in masonry to provide a secure fit. Drop-in anchors work similarly, designed to be set into concrete for a strong, permanent hold, making them unsuitable for hollow walls or materials, as they rely on solid backing to function effectively.