In terms of design principles, what does 'robustness' refer to?

Robustness in design principles primarily refers to the reliability and stability of a system, ensuring that it can continue to function correctly under varying conditions. This encompasses the system's ability to handle errors or unexpected inputs gracefully without crashing. In this context, when we say that robustness prevents computer crashes, we highlight that a robust system is built to endure unforeseen circumstances, such as incorrect user inputs or hardware failures, thus minimizing the chances of a complete breakdown.

While the other concepts mentioned are important for user experience and interface design—such as allowing users to make mistakes, ensuring easy navigation, and focusing on high contrast visuals—they do not embody the core definition of robustness. Instead, they focus on usability and accessibility aspects that enhance user interaction but do not necessarily relate to the system's fundamental stability and reliability. Robustness is more about the resilience of the system's architecture, making option C the most accurate reflection of this principle.