A financial institution requires a secure and compliant way to archive financial transaction data on GCP. Which GCP service provides a cost-effective and compliant solution for long-term data retention?

Google Cloud Storage (GCS) is the correct choice because it offers various storage classes, including Archive and Coldline, which are highly cost-effective for long-term data retention with infrequent access, making it ideal for archiving financial transaction data. GCS also provides robust security features, data immutability, and compliance certifications crucial for financial institutions. Google Cloud BigQuery is a data warehouse for analytics, not primarily for cost-effective long-term archiving. Google Cloud Data Catalog is for metadata management and discovery. Google Cloud Storage Transfer Service is for moving data, not storing it. Cloud Data Loss Prevention (DLP) is for identifying and protecting sensitive data, not for storage itself.