Which of the following steps should be taken last in a brainstorming session?

The last step in a brainstorming session should indeed be the selection of the best ideas based on established criteria. This is the culmination of the brainstorming process, where participants review the generated ideas, assess them against predetermined criteria such as feasibility, relevance, and impact, and identify which ones stand out as viable solutions to the problem at hand.

This final step is critical as it allows for the evaluation of creativity while providing a structure for decision-making. It ensures that the ideas that best meet the needs of the problem, as well as the goals of the session, are chosen for further development or implementation. Prior steps like brainstorming new ideas, defining the problem, and conducting a warm-up session all contribute to a rich pool of creative thoughts and a clear understanding of the focus, but without the selection process, the session would lack direction and purpose after the ideation phase.