Which physical connection is the fastest?

Fiber-optics is the fastest physical connection.

Fiber-optics is a medium of communication that involves the transmission of information from one location to another by sending light pulses along an optical fiber. The sent light pulses produce an electromagnetic carrier wave which is regulated to transmit information. Fiber optics can transmit information over longer distances and its performance is very high. This medium is used to transmit cable television signals, internet communication and telephone signals.