Final answer:
Adhesive bonds should be loaded in shear to effectively distribute the force across the maximum surface area and to prevent bond failure.
Step-by-step explanation:
Adhesive bonds should be loaded in shear only. This is because adhesives are generally better at resisting shear forces than tension or compressive forces due to the internal molecular structure and the way the adhesive layer is applied and loaded between the surfaces it joins. When a bond is loaded in shear, the load is applied parallel to the plane of the adhesive, which maximizes the surface area over which the force is distributed, making it more effective at holding the bonded materials together. On the other hand, loads applied in tension or compression significantly reduce the effective bonding area and can more easily lead to bond failure. Therefore, the correct answer is B. Shear.