Which access-layer device is capable of low-latency 40 Gb Ethernet switching?

Which access-layer device is capable of low-latency 40 Gb Ethernet switching?
A. Cisco Nexus 5596UP
B. Cisco Nexus 4000
C. Cisco Nexus 3016
D. Cisco Nexus 2232
E. Cisco Nexus 2248