A 30-month-old boy is brought to the office for a well-child visit. His father is concerned because the child does not yet speak in sentences. Review of developmental milestones shows the following findings: Domain Current Abilities Expected by 24 Months Expected by 36 Months Language 15 single words, no phrases Two-word phrases, 50+ words Three-word sentences, 200+ words Social Points, shares toys, parallel play Parallel play, imitates adults Cooperative play, takes turns Motor Runs well, kicks ball, walks stairs Runs, kicks ball, walks stairs Rides tricycle, alternates feet on stairs Cognitive Names pictures, sorts shapes Follows two-step commands Knows colors, understands concepts
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ASignificant language delay with normal social and motor development
BGlobal developmental delay affecting language, social, and motor domains equally
CAge-appropriate development across all domains with expected milestone achievement
DSocial communication disorder with impaired parallel play and sharing behaviors
ENormal language development with delayed gross motor skills for age
✓ Correct answer: A. Significant language delay with normal social and motor developmentThis child has isolated expressive language delay (no two-word phrases by 30 months, expected by 24 months) but normal social (parallel play, sharing) and motor milestones (runs, kicks ball, stairs). This pattern suggests specific language impairment rather than global developmental delay or autism. Requires early intervention and audiology referral. Distractor1 mischaracterizes as global delay when other domains are appropriate. Distractor2 describes normal development. Distractor3 incorrectly identifies autism when social skills are intact. Distractor4 reverses the delay pattern.
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