Software as a Service (SaaS) - Provides a fully managed CRM application accessible over the internet, with the cloud provider handling all updates, security, and compliance, allowing the enterprise to focus on its core business.

Platform as a Service (PaaS) - Offers a development and deployment environment in the cloud, enabling the enterprise to build and manage its own CRM applications without worrying about the underlying infrastructure.

Infrastructure as a Service (IaaS) - Delivers virtualized computing resources over the internet, giving the enterprise full control over the CRM software and the infrastructure it runs on, requiring significant IT maintenance.

None of the above - The enterprise should consider an on-premises solution for better control over its CRM system and data.