What might be the most appropriate test technique to use after changing the risk mitigation approach?

Exploratory Testing is highly suitable after changing the risk mitigation approach because it allows testers to investigate and adapt their testing strategies in real-time based on the new context. When risk mitigation strategies change, there may be new risks or altered behaviors to consider. Exploratory Testing facilitates a more intuitive and unscripted approach, enabling testers to explore the application dynamically, assess how these changes impact its functionality, and uncover potential issues that may not follow typical scripted test cases.

This technique focuses on using the tester's knowledge, creativity, and intuition to discover defects and gain insights into the application’s behavior. It is especially valuable in scenarios characterized by uncertainty and evolving requirements, which often accompany changes in risk strategies.

Other techniques mentioned may have their strengths in specific contexts, but they generally rely on predefined behaviors or specifications. In contrast, Exploratory Testing thrives in environments where conditions are fluid, making it the most appropriate choice in this particular situation.