B and D. Updating the host-based intrusion prevention system is important. Without the latest signatures, the HIPS will not be at its best when it comes to protecting against malware. Also, disabling unused services will reduce the attack surface of the OS, which in turn makes it more difficult for attacks to access the system and run malicious code. Disabling the data leakage prevention device would not aid the situation, and it would probably cause data leakage from the computer. Installing a perimeter firewall won't block malicious software from entering the individual computer. A personal firewall would better reduce the attack surface of the computer, but it is still not meant as an antimalware tool. Updating the NIDS signatures will help the entire network, but might not help the individual computer. In this question we want to focus in on the individual computer, not the network. In fact, given the scenario of the question, you do not even know if a network exists.