The CSIRT is reviewing the lessons learned from a recent incident. A worm was able to spread unhindered throughout the network and infect a large number of computers and servers. Which of the following recommendations would be BEST to mitigate the impacts of a similar incident in the future? 

Answer options:

A. Install a NIDS device at the boundary.
B. Segment the network with firewalls.
C. Update all antivirus signatures daily.
D. Implement application blacklisting.

B