What aspects of beer taste do hops contribute to?

Hops primarily contribute to the bitterness, flavor, and aroma of beer. The bitterness is a critical aspect, balancing the sweetness of the malt and providing a key element of the overall taste profile. Hops contain alpha acids, which introduce bitterness during the boiling process of brewing. Additionally, hops impart various flavors and aromas depending on the variety used, with different hops providing notes ranging from floral and citrus to earthy and spicy.

The other aspects mentioned in the alternative choices do not accurately represent the role of hops. Sweetness and carbonation are predominantly influenced by the malt and fermentation process, while clarity and mouthfeel relate more to ingredients like malt, yeast, and the overall brewing method rather than hops. Alcohol content is a result of fermentation, and hops do not impact that aspect directly. Thus, the correct choice reflects the specific contributions of hops to the sensory experience of beer.