Which of the following best describes "impervious"?

The term "impervious" best describes something that is resistant to external influences or unable to be affected or penetrated. It implies a strong shield against outside forces, whether those are physical elements, emotional impacts, or external opinions. In this context, something that is impervious remains unaffected or unyielding, indicating strength or resilience.

For instance, a material that is impervious to water will not allow water to pass through it, reinforcing its ability to resist external conditions. This characteristic of impenetrability is at the core of the definition of "impervious," making it the most appropriate choice among the given options.

The other options, such as vulnerable, open to criticism, and subject to change, all imply a susceptibility or lack of resilience, which directly contrasts with what "impervious" conveys. Therefore, "B" clearly encapsulates the essence of the word.