Which type of beer is primarily brewed using a top-fermenting yeast?

The type of beer primarily brewed using a top-fermenting yeast is ale. This style of beer utilizes Saccharomyces cerevisiae, a top-fermenting yeast that works best at warmer temperatures, typically between 60°F and 75°F (15°C to 24°C). This fermentation method allows for the development of a wide range of flavors and aromas, often resulting in beers that are fruity and complex.

On the other hand, lager is brewed with bottom-fermenting yeast, which ferments at cooler temperatures and results in a clean, crisp flavor profile. Stout and wheat beer can also be made using either type of yeast, but they are generally categorized under ales when top-fermented yeast is used. Therefore, because of its brewing method, ale is the clear choice among the options presented.