What is nystagmus in the context of a neurological examination?

Correct answer is B). Nystagmus is a rhythmic, involuntary oscillation of the eyes. This movement can be horizontal (side-to-side), vertical (up-and-down), or rotary (circular). It is commonly assessed during a neurological examination as it may indicate various neurological or vestibular abnormalities. A) Incorrect. While nystagmus is related to eye movements, it does not involve an inability to coordinate and control eye movements, nor does it typically result in abnormal head posture. C) Incorrect. Nystagmus is not a type of tremor that affects the hands and fingers. It is specific to eye movements. D) Incorrect. Nystagmus does not involve involuntary movements of the tongue; it primarily affects the eyes and their movement.