An Architect Needs to Plan a Very High Density (VHD)

An architect needs to plan a very high density (VHD) wireless network at a large events venue, at which thousands of attendees are expected. The architect plans to deploy a cluster of Mobility Controllers (MCs) to control the APs. It is important to support seamless roaming for wireless devise across the venue. What should the architect ensure for the network services?

A) DHCP servers can support a high number of scopes with a /24 size.
B) A third-party firewall integrates with ClearPass to filter the guest user traffic.
C) A domain CA is set up to deploy certificates to a high volume of guest devices.
D) DHCP and DNS servers are carrier-grade and support a low transaction time.