**Core Concept:** Microsporum audonii is a fungus that can cause hair infections, particularly onychomycosis (fungal nail infections). Woods lamp is a device that detects certain molecules emitted by fungi under UV light, which can aid in diagnosis.

**Why the Correct Answer is Right:** Under a Woods lamp, Microsporum audonii will emit a blue-fluoresce color due to the presence of certain molecules called sterols. These sterols are unique to fungal cells and not present in human cells, making them useful markers for diagnosing fungal infections.

**Why Each Wrong Option is Incorrect:**

A. This option does not specify a particular color and is likely incorrect because Microsporum audonii will emit a blue-fluoresce color under Woods lamp.
B. This option also does not specify a particular color and is likely incorrect as Microsporum audonii will emit a blue-fluoresce color under Woods lamp.
C. This option also does not specify a particular color and is likely incorrect as Microsporum audonii will emit a blue-fluoresce color under Woods lamp.
D. This option is incorrect because Microsporum audonii will emit a blue-fluoresce color under Woods lamp.

**Clinical Pearl:** Examination under a Woods lamp is a useful diagnostic tool in identifying fungal infections, particularly in cases where microscopic examination or culture may not yield clear results. This technique helps in confirming the presence of fungi and guides the choice of appropriate antifungal therapy.

**Correct Answer:** .