When should a pilot turn inbound while in the procedure turn at FEHXE?

The correct choice is based on standard procedures for executing a procedure turn. In the case of the FEHXE waypoint, pilots are instructed to turn inbound once reaching 4 DME miles from the waypoint. This distance is often specified on approach charts and ensures that the pilot is in the proper position to intercept the localizer or final approach path correctly without overflying the waypoint or turning too late.

Flying 4 DME from FEHXE also allows adequate time and space for the aircraft to stabilize for the approach, providing a safe and efficient transition to the final approach segment. Following this guideline helps maintain the required altitude and positioning needed for successful navigation during the approach phase.

Other distances listed in the options would either lead to an excessively early or late turn, which could compromise safety and adherence to the approach procedure.