Answer:
D. the time and place in which the events of the story happen
The big glacier moved slowly into the valley causing the surface or the sides of the valley to create a U shape.
The answer your looking for would be B.
I hope this helps.
11.) Opportunity is the subject
12.) House is the subject
13.) Mr. Stevens is the subject
14.) Essential facts is the subject
Srry but I'm the verbs