What is the hacker trying to accomplish here?

John is the network administrator of XSECURITY systems. His network was recently
compromised. He analyzes the log files to investigate the attack. Take a look at the following Linux
log file snippet. The hacker compromised and “owned” a Linux machine. What is the hacker trying
to accomplish here?

A.
The hacker is attempting to compromise more machines on the network

B.
The hacker is planting a rootkit

C.
The hacker is running a buffer overflow exploit to lock down the system

D.
The hacker is trying to cover his tracks