Which statement about hydraulic fluid is accurate?

The statement that hydraulic fluid can include additives for improved performance is accurate because hydraulic fluids are specifically formulated to enhance their properties for reliable operation in hydraulic systems. These additives can serve various functions, such as improving lubrication, preventing corrosion, increasing viscosity index, enhancing thermal stability, and providing anti-foaming characteristics.

In hydraulic systems, the performance of the fluid is critical for the efficient and safe operation of machinery. Additives help to ensure that the fluid can withstand a range of temperatures and pressures, maintain its properties over time, and protect the components of the hydraulic system from wear and damage.

While some hydraulic fluids are indeed non-compressible under normal operating conditions, it is an oversimplification to say that they are always non-compressible, as all fluids exhibit some degree of compressibility under extreme conditions. Not all liquids can be used as hydraulic fluid, as it must have specific characteristics to function properly in hydraulic systems, and while water-based fluids exist, many hydraulic fluids are synthetic or petroleum-based to better meet the demands of the system.