What header must be included in an API request in order to provide authentication validation?

Comprehensive and Detailed In-Depth Explanation:

For Vault API authentication:

B. X-Vault-Token : " The token for authentication is set directly as a header for the HTTP API. The header should be either X-Vault-Token: < token > or Authorization: Bearer < token > . " This header carries the client token required to validate the request’s authenticity and permissions.

Incorrect Options :

A. X-Token-Vault : Incorrect naming convention. " Does not follow the standard naming conventions. "

C. X-Token-Creds : Not recognized by Vault. " Does not align with standard authentication headers. "

D. X-Vault-Creds : Invalid for authentication. " Does not correspond to the standard mechanism. "

The X-Vault-Token header is critical for secure API interactions.