Final answer:
Fiber Optics has replaced copper wire for long-distance telephone lines, offering advantages like low loss, high bandwidth, and reduced crosstalk.
Step-by-step explanation:
The technology that has replaced copper wire in long-distance telephone lines is Fiber Optics (Option A). Fiber optic cables consist of strands of glass fibers where light signals, typically from lasers, can travel for many kilometers without significant loss, a property known as low loss. This makes them superior to copper conductors for long-distance communication. In addition, the high bandwidth of fiber optics means that much more information can be transmitted over a single fiber than through copper wires, and the reduced crosstalk ensures that optical signals in one fiber do not negatively interfere with those in adjacent fibers. Although satellite transmission, microwave technology, and DSL have played roles in the evolution of telecommunication, fiber optics have become the backbone for modern long-distance and international communication.