40.The__________eliminates the need for adirect-reversing engine while the gearing allows a suitable propeller speed to be selected.
(A)Controllable Pitch Propeller
(B)Fixed Pitch Propeller
(C)Counter Pitch Propeller
(D)Fixed Jet Propeller

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統計： A(2), B(0), C(0), D(0), E(0) #4007073