正解:B
Explanation
A managed switch is a network device that can be configured to create VLANs (Virtual Local Area Networks), which are logical segments of a network that isolate traffic based on criteria such as function, security, or quality of service. A VLAN can be used to isolate voice traffic on the network, which can improve the performance and security of voice over IP (VoIP) applications. A network tap, a hub, and a DSL filter are not capable of creating VLANs.
Reference: [CompTIA A+ Core 1 (220-1101) Certification Study Guide], page 32.