Yeast is the fungal microorganism among the provided options. It is a unicellular fungus that is eukaryotic with beneficial and harmful effects on humans. While some fungi like molds are multicellular, yeasts are generally unicellular.
The type of fungal microorganism listed among the options provided is yeast. Yeasts are unicellular fungi and are part of the diverse group of eukaryotic organisms with chitin in their cell walls. Unlike bacteria, which lack a true nucleus, or viruses, which are not cellular at all, yeasts possess a nucleus and other organelles, making them eukaryotic.
There are more than 1000 known species of yeasts, found in various environments ranging from the deep sea to the human navel. Some have beneficial uses, including causing bread to rise and beverages to ferment, while others can cause spoilage of food and diseases such as vaginal yeast infections and oral thrush, which is caused by Candida albicans.
Though similar to bacteria in form and size, yeasts are distinguishable by their eukaryotic cell structure. Some fungi, such as molds, are multicellular organisms and can form visible colonies and filaments, but this is not the case with yeasts, which are generally unicellular.