What indication occurs with any flight control system caution?

The indication that occurs with any flight control system caution is the illumination of the PFCS FAIL/RESET push-button switches. When there is a caution related to the flight control system, it often signifies a malfunction or degraded performance in the aircraft's flight control systems. The illumination of these switches is a designed response, alerting the crew to the specific issue at hand and prompting them to take appropriate action. This indication serves as a crucial part of the aircraft's warning system, allowing for quicker identification and troubleshooting of potential problems.

In contrast, other options do not accurately reflect the specific response associated with a flight control caution. The system going into standby or a full reset of all systems might not necessarily be the case, as the flight control systems are often designed to retain some level of functionality. Additionally, sounding an alarm could be part of a broader warning system, but the primary and direct indication for a flight control system caution is specifically the illumination of the PFCS FAIL/RESET push-button switches.