A process allows a LUN to be available to some hosts and unavailable to others. Which of the following causes such a process to become vulnerable?

LUN masking is the name of the access control process being described in the question - it is the mechanism being circumvented, not the cause of the vulnerability.

Data injection refers to inserting malicious data into a data stream or storage system and has no relation to the physical relocation of an HBA or LUN access control bypass.

Data fragmentation describes how data is distributed across non-contiguous storage blocks and has no relationship to HBA-based LUN masking or the resulting access control vulnerability.

LUN masking works by associating a LUN's visibility with the World Wide Name (WWN) of a specific HBA - when an HBA is physically relocated to a different host server, that new host inherits the HBA's WWN and gains unauthorized access to the LUN without any change to the masking configuration, completely bypassing the intended access restriction.