What does Marta do to protect herself and Nick during their plan?

Marta's decision to stay at the bottom with a gun demonstrates her protective stance for both herself and Nick during their plan. By remaining at the bottom, she positions herself to guard their location and provides a layer of safety against potential threats. Holding a weapon implies preparedness to confront any dangers that could arise while Nick is executing his part of the plan, which likely involves a more elevated or exposed position. This approach highlights her role as a protector, prioritizing their security in an uncertain situation.

Each of the other actions mentioned involves different levels of risk and engagement with the environment. Climbing a tree might diminish her ability to protect Nick, searching for wildlife could detract from her focus on safety, and leading them through the swamp could place her and Nick in vulnerable positions. Therefore, her choice to stay behind with a gun underscores a vital aspect of their strategy for dealing with any immediate threats.