What kind of tool is typically used to assess cable loss in fiber optics?

The correct choice is a power meter, which is a tool specifically designed to measure the optical power in fiber optic cables. When assessing cable loss, it's essential to quantify how much light is being lost as it travels through a fiber segment. A power meter reports this loss in decibels (dB) by directly measuring the amount of light entering and exiting a fiber optic link.

Using a power meter involves pairing it with a calibrated light source, which generates a known amount of optical power. The technician measures the power at both the input and output of the fiber optic link. The difference between these two measurements reflects the loss incurred due to factors like fiber attenuation, splice losses, or connector quality.

While tools such as visual fault locators can identify breaks or significant faults in the cable by sending a visible light signal, they do not quantify loss in terms of optical power. Connector mating adapters serve to connect different types of connectors but do not measure cable performance or loss. Launch cables are used to manage the launch conditions for a test signal but are not a direct measurement tool. Thus, the power meter is the most suitable tool for assessing cable loss accurately.