When can vertical separation from a prominent obstruction be discontinued during final approach?

Vertical separation from a prominent obstruction can be discontinued during final approach after the aircraft passes the obstruction. This guideline ensures that the aircraft maintains safe clearance from any obstacles that might interfere with its approach and landing. Once the aircraft has passed the obstruction, it is considered safe to reduce or eliminate the vertical separation requirement because the aircraft is no longer in the vicinity of the obstacle.

In scenarios such as final approaches where precision is critical, it is imperative to move past obstacles safely to avoid potential hazards. The other choices may suggest conditions during which the aircraft is either still at risk of colliding with an obstruction or not yet in a safe position relative to it, thereby making them unsuitable for discontinuing vertical separation.