Some instruments focus on only one facet within a domain.

• A. All instruments test multiple facets within a domain
• B. Some instruments focus on only one facet within a domain
• C. Instruments always test all facets
• D. Instruments never focus on a single facet

Answer: (B)

Understanding how assessments are designed helps explain why some instruments measure just one part of a larger area. In any domain, there are multiple facets or components. Some tools are created to target a single facet for efficient, reliable measurement—useful for quick screening, progress monitoring, or when a specific skill needs to be tracked. Others are broader and aim to capture several facets to represent the overall construct.

So, the statement that some instruments focus on only one facet within a domain is accurate and reflects the variety of assessment tools. For example, in literacy, a task that measures only phonemic awareness focuses on that specific skill, whereas a broader reading assessment might evaluate multiple aspects like decoding, fluency, and comprehension. The other options imply that all instruments do the same thing, which isn’t true, or that they never focus on a single facet, which contradicts how many targeted assessments are designed.