An AI risk manager is reviewing a new generative AI product that creates synthetic patient records for medical research. The product's vendor claims the synthetic records are 'fully anonymized' because they are AI-generated and not copied from real patient records. What is the PRIMARY risk assessment concern with this claim?

B is correct because synthetic data generated by models trained on personal data inherits statistical properties of that data—membership inference attacks can identify whether specific individuals' records contributed to training, and in some cases re-identification of synthetic records is possible. 'AI-generated' is not synonymous with 'fully anonymized.' Proper privacy assessment requires demonstrating that the synthetic data satisfies differential privacy or similar formal privacy guarantees. A (quality) is a research utility concern. C (ISO 27001) is an information security certification concern, not a privacy assessment. D (bias in synthetic data) is also a legitimate concern but secondary to the re-identification risk that directly challenges the anonymization claim.