Final answer:
The best recommendation for Bob would be to use a hybrid deployment with Microsoft 365 and Exchange online, allowing him to retain control of servers and mailbox databases while leveraging the features of the cloud-based services.
Step-by-step explanation:
The best recommendation for Bob in this scenario would be to use a hybrid deployment with Microsoft 365 and Exchange online. This would allow him to retain access and control of servers and mailbox databases while still taking advantage of the features offered by Microsoft 365 and Exchange online.
In a hybrid deployment, Bob can keep his on-premises servers and mailbox databases, but also connect them to the cloud-based services provided by Microsoft 365 and Exchange online. This will give him the flexibility to gradually move his workload to the cloud while maintaining control over his data and infrastructure.
By using a hybrid deployment, Bob can take advantage of features like enhanced security, scalability, and collaboration tools offered by Microsoft 365 and Exchange online, while still having full control over his servers and mailbox databases on-premises.