Which edition of the Bayley Scales is described in the material?

• A. III
• B. II
• C. I
• D. IV

Answer: (A)

Think about how the Bayley Scales editions differ in structure and scoring. The material describes a version that breaks the direct, hands‑on assessment into three main domains—Cognitive, Language, and Motor—and also includes two caregiver-reported areas (Social-Emotional and Adaptive Behavior). This combination of three performance domains plus separate caregiver scales matches the layout of the Bayley Third Edition.

Older editions used a different indexing system (like Mental Developmental Index and Psychomotor Developmental Index) and a different overall organization, while the most recent edition updates norms and some subtest configurations but retains a newer structure rather than reverting to the earlier framework. Seeing three core performance domains with the accompanying caregiver scales is how the Bayley-III is typically described, which is why that edition fits the material described.