For examination of fungus from a sample, uniformly stain by
**Core Concept**
The examination of fungi from a sample typically involves staining techniques to visualize the fungal structures, such as hyphae or spores. The choice of stain depends on the type of fungus and the desired level of detail.
**Why the Correct Answer is Right**
The correct answer is **KOH (Potassium Hydroxide) mount**. KOH is a strong alkali that dissolves the keratin in the skin, allowing the fungal elements to be visualized more clearly. The KOH mount is a simple and effective method for examining fungi, especially in cases where other stains may not be necessary. The KOH solution also helps to break down the cellular debris, making it easier to identify the fungal structures.
**Why Each Wrong Option is Incorrect**
**Option A:** Gram stain - This is incorrect because Gram stain is primarily used for bacterial identification, not fungal.
**Option B:** Mucin stain - This is incorrect because mucin stain is used for highlighting mucin-containing structures in tissues, not for fungal examination.
**Option C:** Methenamine silver stain - This is incorrect because methenamine silver stain is used for highlighting fungal elements, but it is not a uniformly staining technique.
**Clinical Pearl / High-Yield Fact**
The KOH mount is a quick and easy method for examining fungi, and it is often used as a preliminary step before more detailed staining techniques.
**Correct Answer: D. KOH (Potassium Hydroxide) mount**