Which preposition best describes working together?

The phrase "in collaboration" directly conveys the idea of individuals or groups working together towards a common goal. It indicates a cooperative effort where contributions from different parties are combined to achieve a specific outcome.

In contrast, the other options do not encapsulate the essence of working together effectively. "In moderation" suggests a careful or controlled approach, often in relation to consumption or activity levels. "On behalf" indicates that one person is acting in support of or representing another individual or group but does not explicitly convey the idea of joint effort. "For the good of" implies an action taken for the benefit of someone or something, but it doesn’t necessarily indicate cooperation between parties. Therefore, "in collaboration" is the most precise term to describe the concept of working together.