**Core Concept**
Bell's palsy is a form of idiopathic peripheral seventh cranial nerve (facial nerve) palsy, characterized by acute onset of unilateral facial weakness or paralysis. The underlying pathophysiology involves inflammation of the facial nerve within the facial canal, leading to nerve conduction block.

**Why the Correct Answer is Right**
In the acute phase, the treatment of Bell's palsy involves corticosteroids to reduce inflammation and swelling of the facial nerve. Corticosteroids, such as prednisolone, work by inhibiting phospholipase A2, an enzyme involved in the inflammatory response, thereby reducing the swelling and promoting nerve conduction recovery. This intervention is most effective when initiated within the first 72 hours of symptom onset.

**Why Each Wrong Option is Incorrect**
**Option A:** This option does not specify the correct treatment for Bell's palsy, which is corticosteroids.
**Option B:** Physical therapy or exercise may be useful in rehabilitation after the acute phase, but it is not the primary treatment for acute Bell's palsy.
**Option C:** Antiviral medications, such as acyclovir, may be considered in cases where herpes simplex virus is suspected as the cause of Bell's palsy, but they are not the first-line treatment for idiopathic Bell's palsy.

**Clinical Pearl / High-Yield Fact**
Treatment with corticosteroids within the first 72 hours of symptom onset significantly improves the prognosis of Bell's palsy, reducing the likelihood of incomplete recovery.

**Correct Answer: C. Antiviral medications, such as acyclovir, may be considered in cases where herpes simplex virus is suspected as the cause of Bell's palsy, but they are not the first-line treatment for idiopathic Bell's palsy.