What is the attacker doing with these packets?

You notice an unusual increase in activity in your network. You investigate by reviewing logs and analyzing traffic flows. In your analysis, you identify a remote host is sending traffic to your network with random TCP flags set including URG PSH, ACK and FIN.

What is the attacker doing with these packets?

A.
The attacker is attempting a TCP random flag attack.

B.
The attacker is attempting a TCP overflow attack.

C.
The attacker is running an XMAS tree scan.

D.
The attacker is running an idle scan.