Final answer:
When approaching under part 91 on the ILS RWY 3, an RVR visibility of 1700 feet means the pilot has limited visibility. The NOTAM for GEG RWY 3 TDZL OTS states the touchdown zone lights are out of service. In this case, the pilot must discontinue the approach due to the safety concern.
Step-by-step explanation:
When approaching to land at KGEG under part 91 on the ILS RWY 3, after intercepting glideslope, ATC advising that the visibility is 1700 RVR means that the visibility at the runway is 1700 feet Runway Visual Range. RVR is a measure of the horizontal distance a pilot can see down the runway during landing or takeoff. In this case, the visibility is relatively low, which may require the pilot to make a decision based on their personal minimums and the airport's operational guidelines.
In the given NOTAM, GEG 01/145, it states that the touchdown zone lights (TDZL) for runway 3 are out of service (OTS). This means that the lights at the beginning of the runway are not functioning. Regarding the approach, the answer would be (a) The pilot must discontinue the approach, as a NOTAM indicating lights being out of service is a safety concern that may affect the pilot's ability to safely land.