What is digital modulation?

Digital modulation refers to the technique used to encode digital data into an analog signal for transmission over various media, such as fiber optics or radio waves. This process allows digital information, which consists of discrete values (0s and 1s), to be represented by variations in a continuous signal.

The choice indicating "interruption of light waves in a coded sequence" is correct because it captures the essence of how digital signals are transmitted using light in fiber optics. In this context, light waves can be turned on and off to create a sequence of light pulses that represent binary data. This method effectively encodes the digital information into the physical properties of light, such as intensity or presence, allowing it to be decoded properly at the receiving end.

Other options describe different forms of modulation or signal transmission techniques that do not directly relate to the digital encoding process. Continuous wave transmission, for example, is typically associated with analog signal transmission rather than digital. Amplitude modulation of analog signals pertains specifically to analog communication systems, and pulsed signal encoding is a broader category that may not necessarily involve the defined coding sequences typical of digital modulation. Hence, the correct choice highlights the specific method employed in digital modulation, particularly relevant to fiber optic communication.