Cost, transmission speed and data link distance between points will dictate which types of cabling that are required.
For example in a small office Ethernet cabling would be the best choice, as fiber optic cabling would be too expensive and most end devices would not have the required interface.
Transmission speeds would dictate the minimum cable specification:
Cable specifications dictate the cable type and the number of pins:
For running cabling over a long distances (100m+) fiber optic is preferred.
For connecting site offices over long distances leased-lines can be used which using CSU/DSU. In that case the service provider will install cabling.