The most helpful question for Larry to strategize a plan for targeting a specific audience when communicating recent customer satisfaction results is: "What does each group know and not know about the customer satisfaction data?" This question helps Larry tailor the communication based on the existing knowledge and information gaps of different key groups such as call center employees, senior management, and the company-wide audience. Understanding what each group already knows will enable him to customize the messaging appropriately to ensure clarity, relevance, and effectiveness in the communication plan.