The two primary sources of deposits that build up on compressor blades are?

Correct Answer: Option C — Salt spray and lube oil mist.

Salt spray from the marine environment and lube oil mist from engine seals are the primary contaminants that accumulate on compressor blades. These deposits disrupt airflow, reduce compressor efficiency, and can lead to compressor stall or surge, necessitating regular maintenance and cleaning to maintain optimal engine performance.