Explanation:

- Yeast

- Yeast is a microorganism classified as a fungus.

- It consumes sugar and converts it into alcohol and carbon dioxide through fermentation.

- Commonly used in baking and brewing.

- Ketchup

- Condiment made primarily from tomatoes, vinegar, sugar, and spices.

- Not related to fungi or sugar consumption by microorganisms.

- Vinegar

- Acetic acid liquid, typically produced through fermentation of ethanol by acetic acid bacteria.

- Not a fungus and does not consume sugar in the way yeast does.

- Baking Powder

- A leavening agent made up of an acid and a base used for increasing volume and lightening texture.

- Does not involve any fungi; works through chemical reactions.

Yeast is indeed referred to as the "sugar-eating fungus."