Which of the following applies to unfilled hollow masonry piers supporting a beam?

The correct response regarding unfilled hollow masonry piers supporting a beam is based on structural engineering principles that govern the stability and load-bearing capacity of such piers. Specifically, the guideline stating that the unsupported height cannot exceed four times the least dimension of the pier is established to ensure structural integrity and prevent buckling or failure under load.

In essence, this limitation is crucial because it considers both the height and the least dimension. The least dimension is typically taken as the smallest cross-sectional measurement of the pier, which directly relates to its ability to withstand compressive forces. By capping the unsupported height at four times this dimension, you maintain a safer construction practice that ensures stability even when subjected to various loads, including dynamic loads and potential lateral forces.

This measure helps prevent potential failure modes that can occur in high, slender piers, thus ensuring that the structure remains safe over time. It's a fundamental aspect of masonry construction standards that builders must adhere to when designing and constructing supports for beams.