正解:C,E
The 401 Unauthorized response indicates that the API call lacks proper authentication. To authenticate a request using a Bearer token, the correct headers must be included. The "Authorization: Bearer <token>" header is the correct format for including a Bearer token in an API request. Additionally, specifying the correct content type can also be important, but in this case, the critical headers are related to authorization.
References:
* Cisco DevNet Associate Study Guide: API Authentication (Chapter 7, Section: Authentication Methods for REST APIs).