The correct answer is C. Service Graph Connectors are ServiceNow-supported integrations when used as delivered or configured within supported boundaries. When an administrator customizes the mappings, the implementation moves away from the supported out-of-box connector behavior. This creates upgrade and support implications because ServiceNow cannot guarantee that customized mappings will remain compatible with future connector updates. The customer becomes responsible for validating, maintaining, and troubleshooting those customizations. Option A is not the primary consequence because customized fields are not simply protected by a special CMDB tag. Option B is incorrect because custom mapping does not automatically block connector execution pending approval. The key risk is supportability and technical debt, making C the correct answer.
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