Which switch is a software-only data center-specialized Ethernet switch?

A.
Cisco Nexus 2000

B.
Cisco Nexus 1000V

C.
Cisco Nexus 7000

D.
Cisco Nexus 5000

Explanation:
The Cisco Nexus 1000V makes use of the Cisco VN-Link capability and consists of two components. The first is software that replaces the vSwitch in each hypervisor, which performs switching between directly attached virtual machines. The second is a standalone physical or virtual appliance that is responsible for the configuration and management of the Nexus 1000V and the integration with VMware vCenter.