What is the definition of beer?

The definition of beer encompasses the key aspects of its production and composition. Beer is an alcoholic beverage made primarily through the fermentation process, which involves converting sugars into alcohol and carbon dioxide. These sugars are derived from malted cereals, typically barley, but other grains like wheat and corn can also be used.

Additionally, hops play a critical role in beer-making, providing bitterness, aroma, and flavor, as well as acting as a natural preservative. This combination of malted grains and hops, along with yeast for fermentation, creates the distinctive characteristics that classify a beverage as beer.

Considering this, the second option aligns perfectly with the fundamental definition of beer and details both the fermentation process and the ingredients involved, making it the most accurate choice.