* B (Cloud OnRamp for IaaS):This allows certain applications to have direct optimized access to public cloud resources while other enterprise traffic remains centralized. OnRamp for IaaS provides dynamic path selection and policy control based on application behavior and performance.
Other options explained:
* A: MPLS L3VPN does not offer cloud-optimized direct access.
* C: SaaS OnRamp is for SaaS applications, not IaaS workloads.
* D: Direct Connect links to the cloud but lacks policy-driven traffic engineering.

* B (Use only secure protocols): Management and administrative access to Internet edge routers must use secure protocols (SSH, SNMPv3, HTTPS) to prevent interception or unauthorized access.
* E (Restrict administrative access): Limiting administrative access via interface ACLs and clear login banners ensures that only authorized personnel can access the system, satisfying compliance and security requirements.
Other options explained:
* A: Filtering infrastructure IP space is good hygiene but not directly related to compliance.
* C: Logging is valuable for operations and incident response but not a compliance control by itself.
* D: EBGP advertisements relate to routing policy, not compliance regulation.

To split an Ethernet domain and ensure isolation of configuration and topology changes, the key mechanism is separating the VLAN management domains. This is achieved through:
* VTP (VLAN Trunking Protocol) domain separation
Each VTP domain controls its own set of VLAN information and will not propagate VLAN changes across domain boundaries. By assigning unique VTP domain names to each half of the network, administrators prevent unintended synchronization of VLANs between switches.
Other options:
* B. VTP password: Adds security but does not separate domains.
* C. STP type: All switches in the domain can run the same or different STP versions and still be part of the same Ethernet domain.
* D. VLAN ID: These can overlap across domains; uniqueness is not required to split domains.