Answer:
C. Crusoe loses his newly built roof to an earthquake
Step-by-step explanation:
Option C is the correct answer.
A character vs. nature conflict is one that actually takes place when a character undergoes/experiences resistance from a natural force. The character can be troubled, disturbed or even tormented by the natural force. The natural force could be weather, earthquake, flood, wilderness, etc.
The above option reveals that Crusoe was actually troubled by an earthquake. Loosing his newly built roof to an earthquake, a natural disaster shows a conflict.