The uploaded study guide gives B. Tangible as the correct answer. The question wording and capitalization are preserved from the source.

Within the accessibility-oriented terminology used elsewhere in the guide, Robust and Perceivable are recognized accessibility principles. “Tangible” is not presented as part of that principle set, so it is the item that does not belong.

Perceivable concerns ensuring that information and interface content can be presented in ways users can perceive. Earlier material in the same guide links perceivability to providing content in formats that can be transformed or accessed in different ways.

Robust also appears in the guide's WCAG-focused material, where it is listed alongside Understandable and Operable.

Option B, Tangible, therefore differs from the terminology used by the guide for digital-accessibility design requirements.

This item is written very briefly in the source, so its intended distinction is best understood by comparing the terminology against the accessibility principles established elsewhere in the same question bank rather than expanding it into a different framework.

For this supplied study guide, the keyed answer is unambiguously B.

Study Guide reference/topics: Accessibility principles, Robust, Perceivable, UX Fundamentals.

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