What best describes the characteristic features of ataxia?

Correct answer is B). Ataxia is characterized by uncoordinated and jerky movements that affect balance and coordination. It results from dysfunction in the cerebellum or its connections, leading to problems with muscle control and voluntary movements. A) Incorrect. The description in option A more closely aligns with chorea, a different movement disorder characterized by involuntary, repetitive, and purposeless movements. C) Incorrect. Ataxia does not involve the loss of muscle tone and flaccidity; this description is more indicative of hypotonia or lower motor neuron lesions. D) Incorrect. Excessive muscle contractions and rigidity are not typical features of ataxia. These symptoms are more often associated with conditions like dystonia or spasticity.