Why can the Onguard posture check not be performed during 802.1x authentication?

Why can the Onguard posture check not be performed during 802.1x authentication?
A . Health Checks cannot be used with 802.1x.
B . Onguard uses RADIUS, so an additional service must be created.
C . Onguard uses HTTPS, so an additional service must be created.
D . Onguard uses TACACS, so an additional service must be created.
E . 802.1x is already secure, so Onguard is not needed.

Answer: C Section: (none) Explanation

Explanation:

OnGuard uses HTTPS to send posture information to the ClearPass appliance. For OnGuard to use HTTPS, it must have access to the network. If a customer requires 802.1x authentication on the wired switch, a separate 802.1x authentication must be used prior to the OnGuard posture check. In this example, an 802.1x PEAP-EAP-MSCHAPv2 authentication is completed first. A separate WebAuth service must be setup with posture checks to use the OnGuard agent.

References: MAC Authentication and OnGuard Posture Enforcement using Dell WSeries ClearPass and Dell Networking Switches (August 2013), page 21