The correct answer is C.
OBJ-5.1: Since the analyst cannot remediate the vulnerabilities by installing a patch, the next best action would be to implement some compensating controls. If a vulnerability exists that cannot be patched, compensating controls can mitigate the risk. Additionally, the analyst should document the current situation to achieve compliance with PCI DSS. The analyst will likely not remove the terminals from the network without affecting business operations, so this is a bad option. The analyst should not build a custom OS image with the patch since this could void the support agreement with the manufacturer and introduce additional vulnerabilities. Also, it would be difficult (or impossible) to replace the POS terminals with standard Windows systems due to the custom firmware and software utilized on these systems.