Considering the organization's need for scalability and business continuity with variable workloads, a hybrid cloud model is the best option. The hybrid cloud allows sensitive data to be kept on a private on-premises or private cloud infrastructure for security and compliance, while also enabling the organization to leverage public cloud resources during demand spikes, ensuring cost-effectiveness and scalability (known as cloud bursting). Public cloud would be less secure for sensitive data, and private alone wouldn't provide the necessary scalability. A multicloud strategy could overcomplicate the infrastructure without offering a specific benefit for demand spikes.