What is the type of loss in a cable plant that is not frequency-dependent?

Flat Loss is the correct choice because it refers to a consistent amount of loss that occurs across a range of frequencies. This type of loss does not vary with frequency, which distinguishes it from other types of losses that can be frequency-dependent, such as insertion loss, cable loss, and return loss. Flat Loss typically represents a total attenuation of the signal due to the physical characteristics of the cable itself, independent of the signal frequency.

Insertion Loss usually varies with frequency due to the potential impact of the connectors or any components within the path of the signal. Similarly, Cable Loss can be frequency-dependent as it often involves factors like resistance and dielectric losses that change with different frequencies. Return Loss reflects the amount of signal reflected back towards the source, which can also vary based on frequency and impedance mismatches in the system. Therefore, Flat Loss stands out as the only type that is inherently independent of frequency variations.