A company wants to enable access to corporate email on smartphones.

The correct solution for this scenario is Mobile Device Management (MDM). According to CompTIA Core 1 (220-1201) mobile device security and management objectives, MDM is specifically designed to manage, secure, and enforce policies on mobile devices used to access corporate resources.

MDM solutions allow organizations to require employees to install management software on their smartphones before accessing corporate email. One of the key features of MDM is data separation, often referred to as containerization, which keeps corporate data isolated from personal data on the same device. This ensures that company information remains secure while still allowing employees to use their devices for personal purposes.

Encryption alone protects data but does not enforce separation or centralized control. Network access control (NAC) restricts which devices can connect to a network but does not manage data on the device itself. Endpoint protection focuses on malware prevention and threat detection, not policy enforcement or data separation.

CompTIA emphasizes MDM as the primary solution for BYOD (Bring Your Own Device) and corporate mobile access scenarios, making it the most suitable and complete answer for this requirement.