I don't really know which one would be the best but if i did have to guess i would say C.
It means to grasp the conce[t of what you searched yesterday
Answer:
the answer is the last sentence
First lets define torrent. Torrent roughly means the violent rush of some sort of liquid. In this case, it seems like the wind during a dark night is being compared to that of a raging river. Hopefully this helps.