How do you quailify for refrigerant recovery epa certification?

A suction line filter is added to the system for a different purpose than the liquid line dryer. A suction line filter is added:

A : to keep acidic oil in the system from working its way back into the new compressor.

B because the suction makes the acid removal better.

C because the suction line is cold and full of acid.

D all of the above.