In a public switched telephone network, what portion of the network is known as the local loop?

a.
It is the portion of the network from the remote switching facility to the central office.

b.
It is the inside wire within the residence or business that connects to the NIU.

c.
It is the portion that connects any residence or business to the nearest central office.

d.
It is the portion of the network between the NIU and the remote switching facility.