An administrator needs to deploy a two-node cluster on a new ROBO Site.

To maintain high availability in the case of a node failure in a two-node cluster, a Witness VM is required. Therefore, the correct answer is A. The Witness VM acts as a tie-breaker and arbitrator in the event of a split-brain scenario, where both nodes lose connectivity to each other, to ensure that only one node continues to operate and serve workloads. It is also recommended to use a high-performance network to minimize network latency between the two nodes and the Witness VM.