What aspect of hydraulic systems allows them to transmit power?

Hydraulic systems rely on the principle of fluid mechanics to transmit power efficiently. The key aspect that allows hydraulic systems to transmit power is the use of pressurized fluid—specifically oil. When oil is pressurized within a closed system, it creates a force that can be directed to perform work, whether that involves moving machinery, lifting loads, or controlling various actuators.

While the options mentioning motors and actuators highlight important components that interact with the hydraulic system, it is the pressurized oil that fundamentally enables the transmission of power. The combination of these elements, including the pressurized oil, serves to create a functional hydraulic system capable of transmitting power effectively.

Thus, the correct answer encompasses all these aspects, reinforcing that it's the integration of pressurized fluid along with motors and actuators that provides the overall capability to transmit power within hydraulic systems.