**Core Concept**
Akathisia is a movement disorder characterized by subjective feelings of restlessness and objective signs of agitation, often associated with the use of antipsychotic medications. The pathophysiology of akathisia is thought to involve an imbalance in dopaminergic and serotonergic neurotransmission.

**Why the Correct Answer is Right**
The drug of choice for akathisia is typically a beta-blocker, specifically propranolol. This is because beta-blockers can help to alleviate the symptoms of akathisia by reducing the activity of the sympathetic nervous system, which is thought to contribute to the development of the disorder. Propranolol is a non-selective beta-blocker that can bind to both beta-1 and beta-2 adrenergic receptors, which are involved in the regulation of heart rate, blood pressure, and other physiological responses.

**Why Each Wrong Option is Incorrect**
**Option A:** Haloperidol is actually an antipsychotic medication that can cause akathisia as a side effect, rather than treating it.
**Option B:** Benzodiazepines, such as alprazolam, can sometimes be used to treat akathisia, but they are not the first-line treatment and can have significant side effects.
**Option C:** Anticholinergic medications, such as trihexyphenidyl, are sometimes used to treat extrapyramidal side effects of antipsychotic medications, but they are not typically used to treat akathisia.

**Clinical Pearl / High-Yield Fact**
Beta-blockers, such as propranolol, are often used to treat akathisia because of their ability to reduce the activity of the sympathetic nervous system, which is thought to contribute to the development of the disorder.

**Correct Answer:** C. Propranolol