Final answer:
Precision Radar Monitoring Service (PRMS) is the service that permits aircraft recovery when visibility and cloud ceiling are below non-precision instrument approach minimums.
Step-by-step explanation:
The question refers to an aviation service that allows aircraft to be redirected or recovered when the cloud ceiling (CIG) or visibility (VIS) is less than the minimum required for non-precision instrument approaches. The correct answer is b. Precision Radar Monitoring Service (PRMS). PRMS is designed to assist aircraft in these situations, ensuring a higher level of safety when the prescribed minimums are not met. It is different from Ground Control Intercept, Positive Control Service, or Airborne Intercept Service in terms of its application and objective during flight operations. An example of how PRMS might be utilized includes situations where an airfield is in a location that makes it susceptible to frequent low visibility and cloud ceiling, necessitating additional monitoring for approaching aircraft.