Which two- factor authentication solution would resolve the gaps in the current CGE environment, and meet the business and security requirements based on the current client types in use?

A physical token, such as a hardware security key or an OTP token, provides a strong 'something you have' factor for two-factor authentication, significantly enhancing security by requiring possession of a physical item in addition to a password. This solution directly addresses the need for strong 2FA.

A complex Active Directory password enforced by Group Policy only enhances the 'something you know' factor and does not provide two-factor authentication, as it still relies on a single authentication factor.

RADIUS authentication with an Employee ID Number alone does not constitute two-factor authentication; the ID number is typically an identifier or a 'something you know' factor, but it is not a distinct second factor unless combined with another secret or biometric.