A network technician is responsible for an extensive enterprise network. The network has hundreds of hosts on the same broadcast domain, reducing performance. The technician needs to find a solution to improve security and mitigate excessive broadcast traffic. What is the solution?

Abstract network

a$.$

Domain Keys Identified Mail $($DKIM$)$

b$.$

Virtual private network $($VPN$)$

c$.$

Sender Policy Framework $($SPF$)$

d$.$

Virtual LAN $($VLAN$)$