A nurse is assessing a I-month-old infant at a pediatric office. Which of the following findings requires a referral for further care?

Rationale: A. Femoral head remains in the acetabulum during the Barlow maneuver: This is a normal finding, indicating that the hip joint is stable and not dislocated. B. Symmetric gluteal and thigh skin folds: Symmetry suggests normal hip alignment and absence of hip dysplasia. C. Equal leg length: Equal leg length is expected and indicates no hip dislocation. D. Limited hip abduction: Limited abduction in a 1-month-old may indicate developmental dysplasia of the hip (DDH). In DDH, the femoral head does not fully seat in the acetabulum, restricting outward movement. Early diagnosis prevents long-term complications such as gait abnormalities or limb-length discrepancy.