The answer is not easy to guess
The illusion plays with perspective, making it seem ambiguous whether Person 2 is actually standing on the bridge or on the railing. In reality, Person 2 might be on the railing, giving the appearance that they are higher than Person 1. Alternatively, they could both be on different levels of the bridge structure.
Answer:The interpretation depends on how you perceive depth:
If Person 1 appears to be grounded on the bridge’s surface, they are likely the one standing securely on the bridge. If Person 2 seems like they are on the flat section of the bridge (and not the railing), they could be the one standing on it.