Which command enables NPIV on Cisco Nexus 5000 Series Switches and Cisco MDS switches?

Which command enables NPIV on Cisco Nexus 5000 Series Switches and Cisco MDS switches?

A.
switch(config)# npiv enable

B.
switch(config)# npivon

C.
switch(config)# feature npiv

D.
switch(config)# npiv proxy

E.
switch(config)# np proxy-enable