Your Rule Base includes a Client Authentication rule, with partial authentication and standard sign on for HTTP, Telnet, and FTP services. The rule was working, until this morning. Now users are not prompted for authentication, and they see error "page cannot be displayed" in the browser. In SmartView Tracker, you discover the HTTP connection is dropped when the Gateway is the destination. What caused Client Authentication to fail?

A.
You added a rule below the Client Authentication rule, blocking HTTP from the internal network.

B.
You disabled NGX Control Connections in Global Properties.

C.
The browsers’ proxy settings have changed.

D.
You enabled Static NAT on the problematic machines.

E.
You added the Stealth Rule before the Client Authentication rule.