A network administrator is troubleshooting an issue whereupon they able to ping the web server, but unable to web browse to the same web server.
When the administrator telnets to the webserver on port 80, the administrator gets a connection refused message. At which three layers of the OSI model does the problem exist?

A.	Layer 1
B.	Layer 2
C.	Layer 3
D.	Layer 4
E.	Layer 5
F.	Layer 6
G.	Layer 7