**Core Concept**
Oral thrush is a fungal infection of the oral mucosa caused by Candida species, particularly Candida albicans. The infection results from an overgrowth of Candida, which can occur due to various factors such as immunosuppression, antibiotic use, or an altered oral environment.

**Why the Correct Answer is Right**
Oral thrush is also known as **oral candidiasis**. The infection occurs when Candida albicans, a normally commensal yeast, overgrows and adheres to the mucosal surface. This overgrowth is facilitated by factors such as a weakened immune system, the use of broad-spectrum antibiotics, or the presence of dentures. Candida albicans produces enzymes such as secreted aspartic proteinase (Sap) to break down proteins and facilitate its adherence to the mucosa.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not a recognized synonym for oral thrush.
* **Option B:** While oral candidiasis can present with white patches, the term "oral candidiasis" is more specific and widely used in clinical practice.
* **Option C:** This option is incorrect as it refers to a different oral condition.

**Clinical Pearl / High-Yield Fact**
Oral thrush can be prevented by maintaining good oral hygiene, avoiding the use of broad-spectrum antibiotics unless necessary, and considering the use of antifungal agents in immunocompromised patients.

**Correct Answer:** B. Oral candidiasis.