🔍 Key Concepts

• Look at the labels on the diagram such as From Start Air Reservoir (30 bar) and To Air Control Reservoir (7 bar) and think about whether the medium is air or liquid. • Notice the symbol at the left marked A with several discrete positions (I, II, III, IV) and a return spring, and consider what that tells you about how many positions the control can select. • The title at the top of the illustration mentions Control Air Pressure-Reducing Unit Valves Group; relate that wording to each of the answer choices.

💭 Think About

• Ask yourself: Is this system using compressed air or hydraulic fluid? Which choices match that working medium? • Consider whether the control seems to move through many continuous positions, or a limited number of fixed positions. Which wording in the choices best matches a valve group with discrete steps and detents? • Look at how the incoming high pressure (30 bar) is reduced before going to the air control reservoir (7 bar). Which option specifically suggests pressure reduction and conditioning rather than just positioning?

✅ Before You Answer

• Verify whether the symbols and labels clearly indicate pneumatic (air) operation instead of hydraulic fluid. • Confirm that the main valve shows several fixed positions rather than infinitely variable movement. • Check which answer choice directly refers to pressure-reducing and filtering/conditioning of control air, matching the function described in the title of the illustration.