Which of the following is a characteristic of tardive dyskinesia?

Tardive dyskinesia is primarily characterized by involuntary movements, particularly in the face and extremities. This condition often results from long-term use of certain antipsychotic medications and manifests through repetitive, uncontrolled movements, which can include facial grimacing, lip smacking, and other dyskinetic movements. The recognition of facial grimacing as a hallmark sign of tardive dyskinesia is crucial for diagnosis and management of the condition.

The other options presented do not align with the symptoms associated with tardive dyskinesia. Visual impairment and clouding of the lens are related to different medical issues, while loss of muscle coordination might suggest other neurological conditions but does not specifically relate to the involuntary movements seen in tardive dyskinesia. Understanding the specific characteristic of involuntary movements aids in accurately identifying and addressing this condition in a clinical setting.