**Core Concept**
Bipolar Disorder (BPD) is a complex psychiatric condition requiring pharmacological prophylaxis to manage symptoms and prevent relapse. The goal of prophylaxis is to stabilize mood and prevent episodes of mania or depression.

**Why the Correct Answer is Right**
Carbamazepine (C) is an anticonvulsant that has mood-stabilizing properties, making it effective in preventing manic episodes in BPD patients. Lithium (b) is a well-established mood stabilizer that reduces the frequency and severity of mood episodes. Sodium valproate (e) is another anticonvulsant that has been shown to be effective in preventing manic and depressive episodes in BPD patients. These three options are all commonly used for prophylaxis in BPD.

**Why Each Wrong Option is Incorrect**
**Option A (Chlorpromazine):** Chlorpromazine is a typical antipsychotic primarily used to treat schizophrenia and other psychotic disorders. It is not typically used for prophylaxis in BPD.
**Option D (Zolpidem):** Zolpidem is a sedative-hypnotic used to treat insomnia. It has no role in the prophylaxis of BPD.

**Clinical Pearl / High-Yield Fact**
When choosing a mood stabilizer for prophylaxis in BPD, it's essential to consider potential side effects, including weight gain, tremors, and thyroid dysfunction. Regular monitoring of these side effects is crucial to ensure optimal treatment outcomes.

**✓ Correct Answer: C. bce**