You need to identify which DNS records are required to provide automatic client sign-in for the remote users. Which records should you identify?

A.
two Alias (CNAME) records and one Host (A) record on a public DNS zone

B.
two Service Location (SRV) records and one Host (A) record on an internal DNS zone

C.
two Alias (CNAME) records and one Host (A) record on an internal DNS zone

D.
two Service Location (SRV) records and one Host (A) record on a public DNS zone

Explanation:
External clients use SRV records to locate sign-in servers, and oviously, these have to be located on public DNS zone, as only it is visible to external clients. (http://technet.microsoft.com/en-us/library/gg398758.aspx)