A customer called the help desk to report a network issue. The customer recently added a hub between the
switch and the router in order to duplicate the traffic flow to a logging device. After adding the hub, all the other
network components that were connected to the switch slowed more than expected. Which of the following is
the MOST likely cause of the issue?


A. Duplex mismatch
B. Flow control failure
C. STP malfunction
D. 802.1Q disabled