Which of the following materials is commonly used for the core of optical fibers?

The correct answer highlights that both glass and plastic are indeed commonly used materials for the core of optical fibers.

In optical fiber technology, the core is the central part of the fiber where light transmission occurs. Glass optical fibers, often referred to as single-mode or multimode fibers, are widely used due to their high performance in long-distance communication, low attenuation, and high bandwidth capabilities. Glass fibers utilize a silica base that effectively guides light through total internal reflection.

On the other hand, plastic optical fibers (POF) provide a more flexible and often easier-to-install alternative. POF typically uses polymer materials that are less expensive and can be simply spliced or connected to devices without complex termination processes. While they might not match glass fibers in terms of distance and performance capabilities, they are advantageous for short-distance applications, such as in-home networks or consumer electronics.

The inclusion of both materials in the answer reflects the diversity and application breadth of optical fibers in various contexts—hence, both glass and plastic serve as important cores for different fiber optics technologies. Therefore, the choice emphasizes the importance of recognizing the various types of optical fibers and the materials used, catering to different operational needs and scenarios.