**Core Concept**
Leukoplakia is a potentially premalignant lesion characterized by the presence of white patches or plaques on the mucous membranes, often in the oral cavity. It is a result of chronic irritation or inflammation, leading to hyperplasia of the epithelial cells.

**Why the Correct Answer is Right**
The treatment of leukoplakia involves the removal of the causative factor, such as tobacco or other irritants, and the application of topical agents to prevent further growth or to promote healing. **Option D**, "Surgery" might be the correct answer because it is often necessary to remove the entire affected area to prevent malignant transformation or to relieve symptoms.

**Why Each Wrong Option is Incorrect**
* **Option A:** "Antibiotics" is incorrect because leukoplakia is not caused by a bacterial infection, and antibiotics would not address the underlying cause.
* **Option B:** "Chemotherapy" is incorrect because leukoplakia is not cancerous in the early stages, and chemotherapy is not indicated as a primary treatment.
* **Option C:** "Radiotherapy" is incorrect because it is not typically used to treat leukoplakia, and might even be contraindicated due to the risk of radiation-induced cancer.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the primary goal of treating leukoplakia is to remove the causative factor and prevent malignant transformation. Regular follow-up appointments are crucial to monitor the affected area for any signs of progression or recurrence.

**Correct Answer:** D. Surgery