为自己加油

Cabin air and equipment cooling exhaust air is filtered by the recirculation air filter and passes through check valves and recirculation fans to the main distribution manifold for redistribution. In the above sentence, 空气经由哪些部件流到主分配总管进行再分配？

A.单向活门，再循环风扇;
B.隔离活门，   空气循环机;
C.配平空气管道，压气机;
D.压气机 ， 再循环风扇;