Which of the following issues can cause a "Loss too low" message to be displayed...

A “Loss too low” message can be displayed after a power adjustment has been provided if there is an issue with unstable optical power levels. Unstable optical power levels can be caused by various factors, such as environmental conditions, fiber aging, equipment malfunction, or configuration errors. Unstable optical power levels can affect the accuracy and reliability of the power adjustment process, which relies on measuring the optical loss between two points in the network. A “Loss too low” message means that the measured optical loss is lower than the expected value, which can indicate a problem with the optical signal quality or integrity. The other issues are incorrect because they either cause a different type of message or do not affect the power adjustment process. References: Nokia Optical Diagnostics and Troubleshooting Course, OAM and Diagnostics Guide