Answer:
The sentence that best explains the central idea of this section of the story is "A woman toils, but moves with subtle power."
Step-by-step explanation:
This excerpt from "Negore, the Coward" by Jack London, uses vocabulary that describes the presence of this woman making comparison with the grace and strength of other elements in nature like animals and plants, but always from the point of view of admiration of her powerful being at the same time that she is able to keep her delicate feminity going.