Adapted from White Fang
by Jack London
And then she found the thing for which she sought. It was a few miles up a small stream that in the summer time flowed into the Mackenzie, but that then was frozen over and frozen down to its rocky bottom—a stream of solid white from source to mouth. The she-wolf was trotting wearily along when she came upon the overhanging, high clay-bank. . . The wear and tear of spring storms and melting snows had under-washed the bank and in one place had made a small cave out of a narrow fissure.
She paused at the mouth of the cave and looked the wall over carefully. Then, on one side and the other, she ran along the base of the wall to where its abrupt bulk merged from the softer-lined landscape. Returning to the cave, she entered its narrow mouth. . . It was dry and cozy. She inspected it with painstaking care, while her companion, who had returned, stood in the entrance and patiently watched her. She dropped her head, with her nose to the ground and directed toward a point near to her closely bunched feet, and around this point she circled several times; then, with a tired sigh that was almost a grunt, she curled her body in, relaxed her legs, and dropped down, her head toward the entrance. . . Her own ears laid their sharp points backward and down against the head for a moment, while her mouth opened and her tongue lolled peaceably out, and in this way she expressed that she was pleased and satisfied.
Which is the best summary of the passage?
A.
The stream is frozen over and frozen down to its rocky bottom. This allows the wolf to cross over where she finds a hidden cave to rest.
B.
The wolf, needing a place to rest, comes upon a cave hidden near a stream. After careful inspection of the cave, the wolf relaxes, and lays down to face the entrance of the cave.
C.
The wolf, traveling upstream, comes to the source of the river. The river is covered in snow. The wolf finds a hidden place to rest.
D.
The cave is hidden near the mouth of the stream. The wolf inspects the wall of the cave and decides that the cave is exactly what she was searching for.