Which header cannot be sent together with an HTTP 407 status code from the ProxySG?

A.
Proxy-Authenticate: Basic=”MyRealm”
B.
Proxy-Authenticate: NTLM=”MyRealm”
C.
Proxy- Authenticate: Kerberos=”MyRealm”
D.
proxy-Authenticate: Negotiate=”MyRealm”
E.
All the above headers can be sent with 407 status code
I choose D
D