A valid authorization token is the correct option when there are no network restrictions configured because the OrionDB account still requires authenticated API requests by default.

By default the service enforces request level authentication and a valid authorization token is presented in the Authorization header and validated on every API call. Tokens prove the caller identity and carry the permissions that determine whether the requested operation is allowed. This ensures that even if the network is open the API does not accept anonymous requests.

Client TLS certificate is incorrect because mutual TLS is an optional configuration and it must be explicitly enabled to require client certificates. It is not the default mechanism used to accept API requests when no network restrictions exist.

Username and password is incorrect because most modern APIs use token based authentication rather than sending raw username and password credentials with each API call. Basic credential schemes are not the default acceptance method for OrionDB accounts.

Google Cloud IAM is incorrect because IAM is an identity and access control system that can be integrated to issue or validate tokens and to grant permissions but the immediate requirement for API requests is possession of a valid authorization token. IAM itself is not the direct transport credential that is sent with each request unless it is used to obtain a token.

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