A network administrator has received reports of intermittent connectivity issues. To diagnose the problem, the network administrator has decided to use tcpdump. Which of the following are the primary functionalities of using tcpdump in this scenario? (Select the two best options.)

A. To monitor network performance and bandwidth usage 

B. To capture and analyze network packets for troubleshooting purposes  

C. To detect and prevent malicious activity on the network 

D. To implement network-based firewall rules