Describe the important reasons for the failure of the optical module function

Due to the pollution and damage of the optical interface, the loss of the optical link increases, resulting in the failure of the optical link. 

Describe the important reasons for the failure of the optical module function: 

A. The optical port of the optical module is exposed to the environment, and the optical port is polluted by dust entering;

B. The end face of the optical fiber connector used has been polluted, and the optical port of the optical module is polluted twice; 

C. The end face of the optical connector with pigtail is improperly used, and the end face is scratched; 

D. Use inferior fiber optic connectors.