What do you think was the most likely cause behind this sudden increase in traffic?

You have been called to investigate a sudden increase in network traffic at pass4sure. It seems that the traffic generated was too heavy that normal business functions could no longer be rendered to external employees and clients. After a quick investigation, you find that the computer has services running attached to TFN2k and Trinoo software. What do you think was the most likely cause behind this sudden increase in traffic?

A.
A distributed denial of service attack.

B.
A network card that was jabbering.

C.
A bad route on the firewall.

D.
Invalid rules entry at the gateway.