which command, when placed on ports that have connected end stations, will allow you to prevent delays in service for end stations by placing a port in blocking mode?

In a high-availability network, which command, when placed on ports that have connected end stations, will allow you to prevent delays in service for end stations by placing a port in blocking mode?

A.
enable backbone fast

B.
enable uplink fast

C.
disable portfast

D.
disable uplink fast

E.
enable portfast