A client is attempting to log in to a web application that requires authentication. The following HTTP
headers are sent by the client:
GET /owa/ HTTP/1.1
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
User-Agent: curl/7.26.0
Host: 10.0.0.14
Accept: */*
Accept-EncodinG. gzip,deflate
The web server is responding with the following HTTP headers:
HTTP/1.1 401 Unauthorized
Content-TypE. text/html
Server: Microsoft-IIS/7.5
WWW-AuthenticatE. NTLM
DatE. Wed, 16 Aug 1977 19:12:31 GMT
Content-LengtH. 1293
The client has checked the login credentials and believes the correct details are being entered.
What is the reason the destination web server is sending an HTTP 401 response?

A.
The username and password are incorrect.

B.
The server has an incorrect date configured.

C.
The client is using the wrong type of browser.

D.
The wrong authentication mechanism is being used.