What are chemical agents defined as?

Chemical agents are substances that can interact with living organisms to produce a physiological effect. This encompasses a wide variety of materials, including gases, liquids, and solids, and they can be used for various purposes, such as controlling behavior or managing crowds. The key aspect of chemical agents is their ability to affect biological systems, which may include inducing irritation, incapacitation, or other responses in individuals exposed to them.

The correct choice highlights that chemical agents exert influence on living organisms, which is essential for understanding their use in various contexts, such as law enforcement or medical applications. This definition encompasses a broad range of substances, emphasizing that their primary characteristic is their impact on biological life. Other options, although they discuss certain characteristics of substances, do not capture the essence of what defines chemical agents effectively.