An attack has been detected in your network system by one of the network engineers. Analyzing the attack, you come to know that the system was accessed through one of the switches where the hacker fed his own VLAN (Virtual Local Area Network) traffic into the port and accessed the network. What kind of an attack has been experienced in this scenario?

a.Double tagging

b.Switch spoofing

c.Incorrect port mode

d.VLAN isolation