Answer:
The slight movement is causing the entire tree to move is the explanation that best describes the movement of the tree in the passage.
Step-by-step explanation:
The description of the movement of the tree does not say that it is an avalanche it makes a comparison to it as the movement and the effect of it is link to each and every part of the tree, one little movement that started all grew as it was advancing until it ended up over the fire that the man had started before.