When preparing temporary mounts of fungal elements, which one of the following acts as a clearing agent to eliminate debris?

The correct answer is 10% KOH, which is widely used in the preparation of temporary mounts for fungal elements. KOH functions as a clearing agent due to its ability to dissolve keratin and other debris present in the sample. This characteristic is particularly important in mycological examinations, as it allows for a clearer view of the fungal structures, such as hyphae or spores, by reducing background material that may obscure these elements.

Using KOH at the specified concentration is effective because it provides a balance that is strong enough to clear the debris without damaging the fungal structures themselves. This makes it an invaluable tool for laboratory professionals when identifying and studying fungi under a microscope. Other substances, while they may have their own applications in different contexts, do not serve the same purpose as KOH in this specific scenario.