1. Context Clues:
- The wayfarer is alone ("no companion but his staff").
- He stops to talk to the innkeeper to avoid feeling something before reaching the first house in the valley.
- The missing word describes a feeling that arises from being alone too long.
2. Eliminating Wrong Options:
- (A) rancor (bitterness) $\rightarrow$ Doesn't fit; no suggestion of anger.
- (B) fatigue (tiredness) $\rightarrow$ Possible, but the focus is on loneliness, not exhaustion.
- (D) camaraderie (friendship) $\rightarrow$ Opposite of what's needed; he lacks companionship.
- (E) companionship $\rightarrow$ Also the opposite; he's avoiding the lack of it.
3. Best Fit:
- (C) seclusion (isolation) $\rightarrow$ Fits perfectly. He talks to the innkeeper to stave off the crushing feeling of being alone.

Key Strategy:
- Focus on the emotional state implied by solitude.
- Eliminate antonyms (D, E) and irrelevant options (A, B).

Answer: (C) seclusion