Which of the following external factors may cause abnormal optical power?

Abnormal optical power can be caused by external factors such as (A) bent optical cables causing increased attenuation or microbends, (B) contaminated connectors reducing transmission efficiency due to dirt or dust, and (C) old optical fibers suffering from aging and degradation that increase loss. (D) Crossed pairs on the ODF (Optical Distribution Frame) is more related to wiring errors but may not directly cause optical power anomalies. HCIP-Transmission stresses proper handling and maintenance of fibers and connectors to maintain optimal optical power levels and network reliability.