Which one of the following statements regarding the PoE $($Power over Ethernet$)$ standard is INCORRECT?

a$.$

The amount of power provided is $15\mathrm{.}4$ watts for standard PoE devices.

b$.$

PoE requires CAT$6$ or better copper cable.

c$.$

Electric current may run over a pair of wires used for data transmission.

d$.$

A device that supplies power for PoE is known as PSE $($Power Sourcing Equipment$).$