Final answer:
The situation best suited for small group communication is when a group needs to brainstorm ideas, as it lends itself to a collaborative and cohesive environment.
Step-by-step explanation:
When considering the scenarios provided, the situation that is best suited for small group communication is when a group needs to brainstorm ideas. Small groups are known for their strong internal cohesiveness, which can enhance the brainstorming process. This setting allows for a free flow of ideas where members can build upon each other's thoughts, leading to a more enriched discussion and potentially innovative solutions. Brainstorming in a small group also allows for quick informal generation of ideas and the opportunity to combine and refine them effectively.