Answer:
The correct answer is B) Joint type. According to the web search results, the fatigue life of a welded structure depends on several factors, such as the loading rate, loading magnitudes, temperature, and quality of fabrication. However, one of the most important factors is the type of welded joint and structure, which determines the stress concentration and the crack initiation and propagation behavior12. Different types of welded joints have different fatigue strength characteristics, and some are more prone to fatigue failure than others. For example, transverse fillet welds are generally weaker than longitudinal fillet welds, and butt welds are stronger than fillet welds34. Therefore, the joint type is a key component of fatigue on a weld.