Dependability in software is defined by which of the following attributes?

Dependability in software is fundamentally about ensuring that the software performs reliably and securely over time, making accuracy and protection against unwanted changes crucial. This attribute encompasses several key characteristics including availability, reliability, safety, and security.

When discussing accuracy, it refers to how correctly the software performs defined tasks and meets its intended purpose. Security from unwanted changes is equally important, as this aspect helps protect the integrity of the software against malicious attacks, bugs, and inadvertent modifications that could cause failures or vulnerabilities.

While the other attributes mentioned are important in their own rights, they do not align as closely with the core definition of dependability. Efficiency of resource use pertains to performance but does not directly ensure reliable behavior. Meeting customer specifications is essential for usability but does not guarantee that the software will operate dependably throughout its lifecycle. Ease of modifications relates to maintainability, which supports dependability indirectly but is not a defining attribute of it. Thus, focusing on accuracy and safeguarding against unwanted changes distinctly highlights the essence of dependability.