Which application-centric infrastructure container is used for IP subnets and can be used to define a Layer 2 boundary?

Which application-centric infrastructure container is used for IP subnets and can be used to define a Layer 2 boundary?
A. bridge domain
B. tenant
C. endpoint group
D. VLAN
E. Private network (layer 3)

Correct Answer: A
Explanation/Reference:
Explanation:
A bridge domain is a construct used to define a Layer 2 boundary within the fabric. A bridge domain can be viewed as somewhat similar to regular VLANs in a traditional switching environment.
1. Specify a bridge domain in the private network.
2. Specify the bridge domain name in the Name field (BD1).
3. Click the + sign next to Subnets to add a public subnet (192.168.1.254/24) to associate with BD1. This public subnet will advertise to ISP1