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Practice quizzes / Austria Theory D Practice Questions - Austria Category D Bus Driving Theory Test Exam / Question 53571
Practice question

What is the primary operating medium used to actuate the service braking system in modern commercial heavy passenger buses?

  1. Hydraulic brake fluid exclusively
  2. Compressed air (Druckluft)
  3. Mechanical steel cables
  4. Continuous engine vacuum pressure

Answer: B — Compressed air (Druckluft)

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