The correct options are
A Yeast is a type of fungi.
B Yeast helps in fermentation.
D Yeast is used in baking industry.
Yeasts are single-celled microorganisms and belong to kingdom Fungi. In an anaerobic (in absence of oxygen) process of obtaining nutrition, yeasts feed on carbohydrates (sugars) and break them down into alcohol, releasing carbon dioxide. This process is called fermentation. They are used to make bread, wine and beer.