How should a driver act if the time to fill the tanks of the air braking system becomes prolonged?

1. AHe will reduce the engine's rotation speed, and thereby improve the work of the compressor.
2. BHe will wait as long as necessary until the tanks fill and ignore the problem.
3. CHe will go to an authorised garage to repair the fault after the tanks have filled, driving slowly and carefully.
4. DHe will check the fuel filter in the system and clean it, if necessary.

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