A hybrid cloud model is the most appropriate choice for this situation because it allows a company to leverage both public and private cloud benefits, maintaining flexibility to handle rapid changes in workload and needs, while keeping sensitive data on-premises for security and compliance reasons. A public cloud model would not provide the necessary control over security for sensitive data, a private cloud would not offer the same level of scalability and operational flexibility, and a multi-cloud approach refers to using multiple cloud services rather than addressing how to handle sensitive information.