Where are the Flight Control Computers signals sent?

The choice that indicates the Flight Control Computers signals are sent to the 4 Actuator Control and Monitoring Units (ACMUs) is indeed the most accurate option. This is because the ACMUs are responsible for executing the commands generated by the Flight Control Computers. They translate the flight control inputs into movements of the control surfaces on the aircraft, such as the ailerons, elevators, and rudder.

The communication between the Flight Control Computers and the ACMUs is essential for the precise and responsive handling of the aircraft, as the ACMUs ensure that the control surfaces are positioned as intended by the pilot's inputs and the flight control system's logic. Given that the Falcon 7X utilizes a fly-by-wire system, which relies heavily on electronic signals rather than traditional mechanical linkages, the role of the ACMUs becomes even more critical in maintaining the aircraft's stability and performance during flight.

The other options refer to different systems which, while important, do not directly receive signals from the Flight Control Computers. For instance, sending signals to the cockpit displays or the navigation system does not relate to the primary function of managing flight control surfaces. Similarly, engine control units are associated more with engine performance and parameters rather than directly with flight control surface management.