The nurse is assessing the neurologic status of a patient who has a late-stage brain tumor. With the reflex hammer, the nurse draws a light stroke up the lateral side of the sole of the foot and inward, across the ball of the foot. In response, the patient's toes fan out, and the big toe shows dorsiflexion. The nurse interprets this result as:

A. The Achilles reflex involves the contraction of the calf muscles, not the fanning of the toes. B. A negative Babinski sign would show the toes curling downward, which is normal for adults, not fanning out. C. A positive Babinski sign, where the toes fan out and the big toe dorsiflexes, is abnormal in adults and typically indicates neurologic damage or dysfunction. D. Clonus involves repeated muscle contractions, not the fanning of the toes.