Which term describes a hydraulically operated brake system?

The term that describes a hydraulically operated brake system is the one that refers specifically to the primary braking system used in vehicles for regular driving purposes. This type of brake system relies on hydraulic fluid to transfer force from the brake pedal to the brake components, effectively applying pressure to the brake pads or shoes and enabling the vehicle to slow down or stop.

Service brakes are the main braking mechanism in a vehicle, designed for everyday use when operating the vehicle under normal conditions. These brakes typically consist of components such as brake pads, rotors, calipers, and hydraulic lines, which work together to create the necessary stopping power.

In contrast, parking brakes are intended to keep a vehicle stationary when parked, emergency brakes are used as a backup system in case of failure of the main brakes, and anti-lock brakes are a safety feature that prevents wheel lock-up during hard braking. While each of these serves a specific function, they do not define the primary hydraulic system responsible for standard braking operations. Therefore, service brakes accurately represent hydraulically operated brake systems found in most vehicles.