Final answer:
When the dietitian decides to discard the melted ice cream and substitute it herself, she is showcasing autocratic leadership. This top-down approach involves quick decision-making without seeking input from others, suitable for immediate action.
Step-by-step explanation:
The Dietitian who decides to throw out melted ice cream and substitute another item for dessert without seeking group input is demonstrating autocratic leadership. This leadership style is characterized by individual control over all decisions with little input from group members. It features a top-down communication pattern, where orders flow from the leader down to the followers. In contrast, a democratic leader would seek input and consensus from others, and a laissez-faire leader would leave the decision to the group members. The autocratic leader takes charge and makes quick decisions, which can be necessary in situations that require immediate action or when dealing with inexperienced team members.