Which of the following is NOT a mobility operation command?

The command "initialize" is not considered a mobility operation command in the context of VPLEX operations. Mobility operation commands are typically focused on managing the movement and synchronization of virtual volumes across storage resources, such as starting a mobility process, committing changes once a move or migration is complete, and removing any associated tasks or processes.

In contrast, "initialize" generally refers to the setup or preparation of a system or resource. It is not specifically linked to the mobility operations that involve transferring, managing, or synchronizing data between different locations in a storage environment. The other options—start, commit, and remove—directly relate to initiating, finalizing, or deleting mobility tasks, making them appropriate within the context of mobility operations.