C and D directly address the stated CPU-contention risk before adding VCF Automation to an already heavily utilized management cluster.

C is correct because VCF Automation adds substantial management-plane compute demand. VCF 9 planning guidance emphasizes verifying that the underlying management-domain infrastructure has sufficient CPU and memory capacity before deploying optional services such as VCF Automation. Adding ESX hosts increases the available physical CPU capacity and is the appropriate response when management-cluster resource pressure already exists. Broadcom similarly recommends scaling the physical cluster by adding ESX hosts when management infrastructure is under resource pressure rather than weakening appliance resource guarantees. ( VMware Blogs )

D is correct because a 1:1 vCPU-to-pCPU ratio eliminates CPU overcommitment for the relevant management workloads and therefore minimizes CPU Ready/contention risk. Broadcom defines CPU overcommitment as total allocated vCPUs divided by physical CPU cores; keeping the ratio at 1:1 provides the most conservative and predictable CPU scheduling model.

A addresses memory reclamation, not CPU contention. B would reduce guaranteed resources and can worsen performance predictability. E is unnecessary; manual NUMA placement is not the normal VCF remediation for management-cluster CPU pressure.

Study Guide References/Topics: VCF Automation Physical Design; Management Domain Sizing; VCF Automation Resource Requirements; CPU Contention; vCPU-to-pCPU Ratios; Management Cluster Expansion and Capacity Planning.