A hiker seals a plastic bag that contains dried fruits before he climbs a mountain. What will most likely happen to the plastic bag as the hiker reaches the top of the mountain?

As the hiker climbs, the air pressure outside the sealed bag decreases. The air trapped inside the bag then pushes outward more strongly than the surrounding air pushes inward, so the bag expands. The best choice is “The bag will expand.”

AI-written and checked against the verified answer.