What proxy tool has Gerald’s attacker used to cover their tracks?

Gerald, the Systems Administrator for Hyped Enterprises, has just discovered that his network has
been breached by an outside attacker. After performing routine maintenance on his servers, he
discovers numerous remote tools were installed that no one claims to have knowledge of in his
department. Gerald logs onto the management console for his IDS and discovers an unknown IP

address that scanned his network constantly for a week and was able to access his network
through a high-level port that was not closed. Gerald traces the IP address he found in the IDS
log to a proxy server in Brazil. Gerald calls the company that owns the proxy server and after
searching through their logs, they trace the source to another proxy server in Switzerland. Gerald
calls the company in Switzerland that owns the proxy server and after scanning through the logs
again, they trace the source back to a proxy server in China. What proxy tool has Gerald’s
attacker used to cover their tracks?

A.
ISA proxy

B.
IAS proxy

C.
TOR proxy

D.
Cheops proxy