You are a junior technician at KVM Solutions. They have just received a query from a university who wants their network connection to be set up$.$ You have been tasked with sketching a diagram for the various network devices that will be used to establish the connection. Which of the following options would you apply to identify the routers in that connection?

a$.$ A brick wall symbol

b$.$ A rectangular box, but with squiggly lines on the front

c$.$ A small rectangular box, which contains four arrows pointing in opposite directions

d$.$ A hockey$-$puck shape with two arrows pointing inward and two arrows pointing outward