Which term refers to a system characterized by conflict or opposition?

The term "adversarial" refers to a system that is marked by conflict or opposition. It originates from the root word "adversary," which denotes someone who opposes or fights against another. In contexts such as law, politics, or competitive environments, an adversarial system is one where parties or entities are positioned against one another, often to present conflicting arguments or to compete for differing outcomes. This captures the essence of opposition inherent in the term.

The other terms present different meanings. "Didactic" relates to teaching or intended to instruct, often with a moral lesson. "Untenable" describes a position or argument that cannot be maintained or defended, particularly in the face of objection, but it doesn't inherently convey the sense of ongoing conflict. "Composite" refers to something made up of various parts or elements, which does not imply opposition or conflict between those elements. Thus, "adversarial" is the only term that specifically encapsulates a system characterized by conflict.