Which of the following findings is considered normal during a physical examination of a 3-year-old child?

This question assesses knowledge of pediatric growth and development milestones for a toddler transitioning into the preschool stage. Application of physical, cognitive, and language development standards for a thirty-six-month-old child is required to distinguish normal findings from abnormal neurological or developmental delays. Choice A rationale The Babinski reflex, where the big toe dorsiflexes, should disappear by twenty-four months of age as the corticospinal tract matures. Its presence at age three is abnormal and suggests a central nervous system lesion or delayed neurological development. Choice B rationale Hopping on one foot is a gross motor skill usually mastered at age four. While some three-year-olds may attempt it, it is not the standard developmental expectation for this age group, who are more adept at riding tricycles. Choice C rationale By age three, children typically have a vocabulary of about nine hundred words and use three-word to four-word sentences. This linguistic milestone reflects normal cognitive and social development, allowing the child to communicate basic needs and observations effectively. Choice D rationale The absence of stranger anxiety is not a standard physical or developmental finding at this age. While it peaks earlier, children at age three still demonstrate clear preferences for primary caregivers and may show wariness toward unfamiliar individuals.