Final answer:
The statement that ESXi host remediation cannot be run in parallel is false. It is possible to configure parallel remediation, provided the appropriate license is in place and the user is aware of the associated risks.
Step-by-step explanation:
In regards to the statement about ESXi host remediation, the correct answer is B) False. By default, VMware vSphere Update Manager does remediate ESXi hosts in a cluster sequentially to ensure minimal downtime and maintain cluster stability. However, it is possible to configure vSphere Update Manager to perform remediation in parallel on multiple hosts simultaneously, if you have the correct license and understand the risks involved, such as potential reduced cluster redundancy during the process.