The milestones of a 3-year-old child are considered delayed if he is unable to:
**Core Concept**
The development of motor and cognitive skills in children follows a predictable timeline. Delayed milestones in a 3-year-old child may indicate a developmental disorder or neurological condition.
**Why the Correct Answer is Right**
The correct answer is related to the child's ability to use verbal and nonverbal communication skills. At 3 years of age, children typically have a vocabulary of around 1,000 words and can engage in simple conversations. They also start using gestures and pointing to communicate. Delayed verbal and nonverbal communication skills can be an early indicator of autism spectrum disorder (ASD) or other developmental delays.
**Why Each Wrong Option is Incorrect**
**Option A:** Speaking in complete sentences - While 3-year-olds may start using short sentences, this skill is typically developed later, around 4-5 years of age.
**Option B:** Riding a tricycle - This is a gross motor skill that children usually master around 3 years of age, so it's not a delayed milestone at this age.
**Option C:** Drawing simple shapes - Children typically start drawing simple shapes and lines around 2-3 years of age, so this is not a delayed milestone.
**Clinical Pearl / High-Yield Fact**
Remember the "Red Flags" for developmental delays: lack of smiling by 6 months, no single words by 16 months, and no two-word phrases by 24 months. These can be early indicators of a developmental disorder.
**Correct Answer:** D. Using verbal and nonverbal communication skills to convey needs and wants.