A financial institution is planning to migrate its operations to the cloud to leverage the benefits of cloud computing while ensuring the highest levels of security and compliance with regulatory requirements. The institution deals with highly sensitive customer data and must adhere to strict data protection laws. It requires a cloud deployment model that not only provides robust security and complete control over its infrastructure but also offers the flexibility to scale resources dynamically during peak operational periods to handle increased workloads efficiently. Additionally, the institution is concerned about optimizing costs without compromising on security or compliance. Given these requirements, which of the following cloud deployment models would BEST meet the institution's needs? (Choose one option from A to D)