Which term signifies an agreement between all parties involved?

The term that signifies an agreement between all parties involved is "consensus." Consensus is a collective decision-making process, where all members of a group reach a mutual agreement or shared understanding on a particular issue or course of action. This process emphasizes collaboration and inclusivity, ensuring that everyone's opinions and concerns are considered, ultimately leading to a harmonious outcome that reflects the group's collective viewpoint.

In contrast, the other terms do not imply this same level of agreement. Confluence refers to the point where two rivers or ideas meet but does not necessarily imply agreement among parties. Cooperation involves individuals or groups working together towards a common goal, but it doesn’t explicitly indicate that all parties have reached an agreement. Contention highlights disagreement or conflict, which is the opposite of a harmonious consensus among participants. Thus, consensus is the most accurate representation of an agreement among all parties involved.