For a wall with shear panels, the edges of openings that materially affect strength must be designed primarily to transfer what?

In the context of shear panels in a wall assembly, the edges of openings that materially affect the overall strength must primarily be designed to transfer shear stress. Shear panels are critical elements within a structure because they provide resistance to lateral forces, such as wind or seismic activity. When openings are present, such as windows or doors, they can disrupt the continuity of the shear panel, leading to vulnerabilities in the wall's structural integrity.

To mitigate these issues, engineers must ensure that the edges of these openings are capable of transferring shear forces that may arise during events like high winds or ground shaking. Proper design helps maintain the wall's overall strength and prevents potential failures. Therefore, ensuring that the areas around openings can handle the shear stresses is essential for the structural safety of the building. This is why the correct answer focuses on shear stress as the load type that the edges need to accommodate effectively.