The correct answer is: "A unique OCID is automatically generated for each secret and remains unchanged even when creating a new secret version." The statement that is NOT valid about managing secrets in the OCI Vault service is: "A unique OCID is automatically generated for each secret and remains unchanged even when creating a new secret version." In OCI Vault, a secret is identified by its OCID (Oracle Cloud Identifier), which is a unique identifier for each resource in Oracle Cloud Infrastructure. However, when a new secret version is created for an existing secret, the OCID remains the same for the secret itself, but a new OCID is generated for the secret version. This allows you to track and manage different versions of a secret while maintaining a consistent OCID for the secret itself. The other statements mentioned are valid: You can manually create new secrets as well as new secret versions using the OCI Console. This means you have control over creating and managing secrets within the Vault service. A secret reuse rule prevents the use of secret contents across different versions of a secret. This ensures that each secret version maintains its own unique set of contents and avoids accidental reuse or sharing of secrets across versions. By default, new secret versions automatically expire in 90 days unless you configure an expiry rule. This helps enforce good security practices by automatically rotating secrets periodically, reducing the risk of unauthorized access in case of compromise. Therefore, the statement that is NOT valid is the one regarding the uniqueness and consistency of the OCID when creating new secret versions.