Refer to the exhibit.

A company needs a new wireless solution for its large campus with multiple buildings. The campus has
8,000 users, and the company also has 1000 users who use VIA concurrently. The customer requires full redundancy for the Mobility Controllers (MC), including seamless roaming and stateful failover for the main site.
Buildings are close enough together for users to roam between them. The exhibit shows the existing wired network.
The architect plans to propose:
500 APs (100 each in Building 1 and 2, 200 each in Buildings 3 and 4).

two 7030 MCs

two 7220 MCs

one MM appliance

The exhibit shows the existing wired network at the main site.
Where should the architect plan to connect the MCs? (Potential locations are numbered in the exhibit.)