The ability to stack switches using cisco stackwise technology provides A number of important benefits to the customer, which of these is A benefit of cisco stackwise?（）

• A、allows cisco smart switches to be incorporated into the stack
• B、allows multiple switches to be managed as A single device.
• C、enables switches in multiple wring closets to provide failover for each other
• D、eliminates the need to purchase smartnet on individual switches in the stack