Which of the Following Statements Regarding IS-IS Authentication Are True

Which of the following statements regarding IS-IS authentication are true?

A) After area authentication is configured on a router, IIH PDUs, SNPs, and LSPs sent by the router must carry an authentication TLV.
B) Interface authentication can authenticate Level-1 and Level-2 Hello PDUs.
C) After interface authentication is configured on a router, IIH PDUs sent by the router must carry an authentication TLV.
D) Two routers can establish a neighbor relationship when they are configured with area authentication and interface authentication, respectively, and are configured with the same authentication password.