Real-time replication to a second data center means that any changes made to the primary data center are immediately copied to the secondary data center. This can improve data availability and performance, but also introduces the risk of propagating malicious or erroneous changes to the backup data center. If a cybersecurity attack compromises the primary data center, it may also affect the secondary data center, making it difficult or impossible to recover from the attack using the replicated data. Therefore, option C is the greatest risk associated with this change.

Option A is not correct because version control issues are more likely to occur with batch processing backup, which may create inconsistencies between different versions of the data. Option B is not correct because real-time replication may reduce system performance at the primary data center, but it may also improve system performance at the secondary data center by reducing latency and network traffic. Option D is not correct because although real-time replication may increase IT investment cost, this is not a risk but a trade-off that the organization has to consider.