Final answer:
During the brainstorming part of the activity, the best ideas are most likely to surface.
Step-by-step explanation:
The best ideas are most likely to surface during the brainstorming part of the activity when brainstormers work at the process for a long period of time. Brainstorming involves generating possible ideas and thoughts quickly and informally. It is a stage in the writing process where a wide variety of ideas and possible solutions are explored for a specific problem or topic.