If registering process requires a password and it is not provided, what message will the registrar send?

If registering process requires a password and it is not provided, what message will the registrar send?
A . 400 Bad request
B . 401 Unauthorized
C . 402 Payment required
D . 403 Forbidden
E . 404 not found

View Answer

Answer: B

Explanation:

Reference: https://www.ietf.org/rfc/rfc3261.txt (See 21.4.2 401 Unauthorized).