## **Core Concept**
The Wood's lamp examination is a diagnostic tool used in dermatology to help diagnose various skin conditions. It emits ultraviolet (UV) light, which can cause certain skin conditions to fluoresce. Tinea versicolor, a common skin condition caused by an overgrowth of yeast on the skin, exhibits a characteristic fluorescence under the Wood's lamp.

## **Why the Correct Answer is Right**
Tinea versicolor, caused by Malassezia yeast, exhibits a **yellowish-green** or **coppery-orange** fluorescence under the Wood's lamp. This is because the Malassezia yeast produces porphyrins, which fluoresce when exposed to the UV light emitted by the Wood's lamp. This characteristic fluorescence helps in the diagnosis of tinea versicolor.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because tinea versicolor does not exhibit blue fluorescence under the Wood's lamp.
- **Option B:** This option might seem plausible but is incorrect because, although some conditions exhibit white fluorescence, tinea versicolor is specifically known for its yellowish-green or coppery-orange fluorescence.
- **Option D:** This option is incorrect because tinea versicolor does not exhibit blue-green fluorescence; the correct description is yellowish-green or coppery-orange.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl to remember is that when using a Wood's lamp for diagnostic purposes, tinea versicolor characteristically shows a **yellowish-green** or **coppery-orange** fluorescence. This can be a helpful diagnostic clue, especially in cases where the clinical presentation is atypical.

## **Correct Answer:** .