Which of the following best describes the characteristics of acids?

Acids are known for exhibiting characteristic properties that define their behavior in chemical reactions and their interactions with different substances. For example, acids typically taste sour, can conduct electricity when dissolved in water due to the presence of ions, and can react with bases to form salts and water in a neutralization reaction. These properties are essential in identifying substances as acids.

Options suggesting that acids decrease hydrogen ion concentration or increase hydroxide ions misrepresent the fundamental behavior of acids. Acids increase the hydrogen ion concentration in solution, which is a defining characteristic, while bases are associated with increasing hydroxide ions. Additionally, stating that acids are solely composed of one substance overlooks that acids can be composed of various molecular forms, including complex mixtures. Thus, the choice highlighting the characteristic properties is the most comprehensive and accurate description of acids.