Which type of test assesses vulnerability to attacks and the secure storage of data?

The correct choice is focused on identifying the strengths and weaknesses of a system's security features. A security test evaluates how well data is protected against potential attacks, ensuring that sensitive information is securely stored and can withstand various types of threats. This type of testing often involves simulating attacks to uncover vulnerabilities and assess the effectiveness of security measures in place.

In contrast, usability tests examine how user-friendly and accessible an application is, focusing more on the user experience than on security features. Stress tests evaluate how a system performs under heavy loads or extreme conditions, looking at response times and stability rather than security vulnerabilities. Regression tests check whether recent changes to the code have affected existing functionalities but do not specifically target security aspects. Thus, the emphasis on securing data and assessing vulnerabilities solidifies why this option correctly characterizes the nature of a security test.